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Thursday, October 13, 2022

Euthyphro dilemma

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Socrates

The Euthyphro dilemma is found in Plato's dialogue Euthyphro, in which Socrates asks Euthyphro, "Is the pious (τὸ ὅσιον) loved by the gods because it is pious, or is it pious because it is loved by the gods?"

Although it was originally applied to the ancient Greek pantheon, the dilemma has implications for modern monotheistic religions. Gottfried Leibniz asked whether the good and just "is good and just because God wills it or whether God wills it because it is good and just". Ever since Plato's original discussion, this question has presented a problem for some theists, though others have thought it a false dilemma, and it continues to be an object of theological and philosophical discussion today.

The dilemma

Socrates and Euthyphro discuss the nature of piety in Plato's Euthyphro. Euthyphro proposes (6e) that the pious (τὸ ὅσιον) is the same thing as that which is loved by the gods (τὸ θεοφιλές), but Socrates finds a problem with this proposal: the gods may disagree among themselves (7e). Euthyphro then revises his definition, so that piety is only that which is loved by all of the gods unanimously (9e).

At this point the dilemma surfaces. Socrates asks whether the gods love the pious because it is the pious, or whether the pious is pious only because it is loved by the gods (10a). Socrates and Euthyphro both contemplate the first option: surely the gods love the pious because it is the pious. But this means, Socrates argues, that we are forced to reject the second option: the fact that the gods love something cannot explain why the pious is the pious (10d). Socrates points out that if both options were true, they together would yield a vicious circle, with the gods loving the pious because it is the pious, and the pious being the pious because the gods love it. And this in turn means, Socrates argues, that the pious is not the same as the god-beloved, for what makes the pious the pious is not what makes the god-beloved the god-beloved. After all, what makes the god-beloved the god-beloved is the fact that the gods love it, whereas what makes the pious the pious is something else (9d-11a). Thus Euthyphro's theory does not give us the very nature of the pious, but at most a quality of the pious (11ab).

In philosophical theism

The dilemma can be modified to apply to philosophical theism, where it is still the object of theological and philosophical discussion, largely within the Christian, Jewish, and Islamic traditions. As German philosopher and mathematician Gottfried Leibniz presented this version of the dilemma: "It is generally agreed that whatever God wills is good and just. But there remains the question whether it is good and just because God wills it or whether God wills it because it is good and just; in other words, whether justice and Goodness are arbitrary or whether they belong to the necessary and eternal truths about the nature of things."

Many philosophers and theologians have addressed the Euthyphro dilemma since the time of Plato, though not always with reference to the Platonic dialogue. According to scholar Terence Irwin, the issue and its connection with Plato was revived by Ralph Cudworth and Samuel Clarke in the 17th and 18th centuries. More recently, it has received a great deal of attention from contemporary philosophers working in metaethics and the philosophy of religion. Philosophers and theologians aiming to defend theism against the threat of the dilemma have developed a variety of responses.

God commands it because it is right

Supporters

The first horn of the dilemma (i.e. that which is right is commanded by God because it is right) goes by a variety of names, including intellectualism, rationalism, realism, naturalism, and objectivism. Roughly, it is the view that there are independent moral standards: some actions are right or wrong in themselves, independent of God's commands. This is the view accepted by Socrates and Euthyphro in Plato's dialogue. The Mu'tazilah school of Islamic theology also defended the view (with, for example, Nazzam maintaining that God is powerless to engage in injustice or lying), as did the Islamic philosopher Averroes. Thomas Aquinas never explicitly addresses the Euthyphro dilemma, but Aquinas scholars often put him on this side of the issue. Aquinas draws a distinction between what is good or evil in itself and what is good or evil because of God's commands, with unchangeable moral standards forming the bulk of natural law. Thus he contends that not even God can change the Ten Commandments (adding, however, that God can change what individuals deserve in particular cases, in what might look like special dispensations to murder or stealing). Among later Scholastics, Gabriel Vásquez is particularly clear-cut about obligations existing prior to anyone's will, even God's. Modern natural law theory saw Grotius and Leibniz also putting morality prior to God's will, comparing moral truths to unchangeable mathematical truths, and engaging voluntarists like Pufendorf in philosophical controversy. Cambridge Platonists like Benjamin Whichcote and Ralph Cudworth mounted seminal attacks on voluntarist theories, paving the way for the later rationalist metaethics of Samuel Clarke and Richard Price; what emerged was a view on which eternal moral standards, though dependent on God in some way, exist independently of God's will and prior to God's commands. Contemporary philosophers of religion who embrace this horn of the Euthyphro dilemma include Richard Swinburne and T. J. Mawson (though see below for complications).

Criticisms

  • Sovereignty: If there are moral standards independent of God's will, then "[t]here is something over which God is not sovereign. God is bound by the laws of morality instead of being their establisher. Moreover, God depends for his goodness on the extent to which he conforms to an independent moral standard. Thus, God is not absolutely independent." 18th-century philosopher Richard Price, who takes the first horn and thus sees morality as "necessary and immutable", sets out the objection as follows: "It may seem that this is setting up something distinct from God, which is independent of him, and equally eternal and necessary."
  • Omnipotence: These moral standards would limit God's power: not even God could oppose them by commanding what is evil and thereby making it good. This point was influential in Islamic theology: "In relation to God, objective values appeared as a limiting factor to His power to do as He wills... Ash'ari got rid of the whole problem by denying the existence of objective values which might act as a standard for God's action." Similar concerns drove the medieval voluntarists Duns Scotus and William of Ockham. As contemporary philosopher Richard Swinburne puts the point, this horn "seems to place a restriction on God's power if he cannot make any action which he chooses obligatory... [and also] it seems to limit what God can command us to do. God, if he is to be God, cannot command us to do what, independently of his will, is wrong."
  • Freedom of the will: Moreover, these moral standards would limit God's freedom of will: God could not command anything opposed to them, and perhaps would have no choice but to command in accordance with them. As Mark Murphy puts the point, "if moral requirements existed prior to God's willing them, requirements that an impeccable God could not violate, God's liberty would be compromised."
  • Morality without God: If there are moral standards independent of God, then morality would retain its authority even if God did not exist. This conclusion was explicitly (and notoriously) drawn by early modern political theorist Hugo Grotius: "What we have been saying [about the natural law] would have a degree of validity even if we should concede that which cannot be conceded without the utmost wickedness, that there is no God, or that the affairs of men are of no concern to him" On such a view, God is no longer a "law-giver" but at most a "law-transmitter" who plays no vital role in the foundations of morality. Nontheists have capitalized on this point, largely as a way of disarming moral arguments for God's existence: if morality does not depend on God in the first place, such arguments stumble at the starting gate.

Responses to criticisms

Contemporary philosophers Joshua Hoffman and Gary S. Rosenkrantz take the first horn of the dilemma, branding divine command theory a "subjective theory of value" that makes morality arbitrary. They accept a theory of morality on which, "right and wrong, good and bad, are in a sense independent of what anyone believes, wants, or prefers." They do not address the aforementioned problems with the first horn, but do consider a related problem concerning God's omnipotence: namely, that it might be handicapped by his inability to bring about what is independently evil. To this they reply that God is omnipotent, even though there are states of affairs he cannot bring about: omnipotence is a matter of "maximal power", not an ability to bring about all possible states of affairs. And supposing that it is impossible for God not to exist, then since there cannot be more than one omnipotent being, it is therefore impossible for any being to have more power than God (e.g., a being who is omnipotent but not omnibenevolent). Thus God's omnipotence remains intact.

Richard Swinburne and T. J. Mawson have a slightly more complicated view. They both take the first horn of the dilemma when it comes to necessary moral truths. But divine commands are not totally irrelevant, for God and his will can still effect contingent moral truths. On the one hand, the most fundamental moral truths hold true regardless of whether God exists or what God has commanded: "Genocide and torturing children are wrong and would remain so whatever commands any person issued." This is because, according to Swinburne, such truths are true as a matter of logical necessity: like the laws of logic, one cannot deny them without contradiction. This parallel offers a solution to the aforementioned problems of God's sovereignty, omnipotence, and freedom: namely, that these necessary truths of morality pose no more of a threat than the laws of logic. On the other hand, there is still an important role for God's will. First, there are some divine commands that can directly create moral obligations: e.g., the command to worship on Sundays instead of on Tuesdays. Notably, not even these commands, for which Swinburne and Mawson take the second horn of the dilemma, have ultimate, underived authority. Rather, they create obligations only because of God's role as creator and sustainer and indeed owner of the universe, together with the necessary moral truth that we owe some limited consideration to benefactors and owners. Second, God can make an indirect moral difference by deciding what sort of universe to create. For example, whether a public policy is morally good might indirectly depend on God's creative acts: the policy's goodness or badness might depend on its effects, and those effects would in turn depend on the sort of universe God has decided to create.

It is right because God commands it

Supporters

The second horn of the dilemma (i.e. that which is right is right because it is commanded by God) is sometimes known as divine command theory or voluntarism. Roughly, it is the view that there are no moral standards other than God's will: without God's commands, nothing would be right or wrong. This view was partially defended by Duns Scotus, who argued that not all Ten Commandments belong to the Natural Law in the strictest sense. Scotus held that while our duties to God (the first three commandments, traditionally thought of as the First Tablet) are self-evident, true by definition, and unchangeable even by God, our duties to others (found on the second tablet) were arbitrarily willed by God and are within his power to revoke and replace (although, the third commandment, to honour the Sabbath and keep it holy, has a little of both, as we are absolutely obliged to render worship to God, but there is no obligation in natural law to do it on this day or that). Scotus does note, however that the last seven commandments "are highly consonant with [the natural law], though they do not follow necessarily from first practical principles that are known in virtue of their terms and are necessarily known by any intellect [that understands their terms. And it is certain that all the precepts of the second table belong to the natural law in this second way, since their rectitude is highly consonant with first practical principles that are known necessarily". Scotus justifies this position with the example of a peaceful society, noting that the possession of private property is not necessary to have a peaceful society, but that "those of weak character" would be more easily made peaceful with private property than without.

William of Ockham went further, contending that (since there is no contradiction in it) God could command us not to love God and even to hate God. Later Scholastics like Pierre D'Ailly and his student Jean de Gerson explicitly confronted the Euthyphro dilemma, taking the voluntarist position that God does not "command good actions because they are good or prohibit evil ones because they are evil; but... these are therefore good because they are commanded and evil because prohibited." Protestant reformers Martin Luther and John Calvin both stressed the absolute sovereignty of God's will, with Luther writing that "for [God's] will there is no cause or reason that can be laid down as a rule or measure for it", and Calvin writing that "everything which [God] wills must be held to be righteous by the mere fact of his willing it." The voluntarist emphasis on God's absolute power was carried further by Descartes, who notoriously held that God had freely created the eternal truths of logic and mathematics, and that God was therefore capable of giving circles unequal radii, giving triangles other than 180 internal degrees, and even making contradictions true. Descartes explicitly seconded Ockham: "why should [God] not have been able to give this command [i.e., the command to hate God] to one of his creatures?" Thomas Hobbes notoriously reduced the justice of God to "irresistible power" (drawing the complaint of Bishop Bramhall that this "overturns... all law"). And William Paley held that all moral obligations bottom out in the self-interested "urge" to avoid Hell and enter Heaven by acting in accord with God's commands. Islam's Ash'arite theologians, al-Ghazali foremost among them, embraced voluntarism: scholar George Hourani writes that the view "was probably more prominent and widespread in Islam than in any other civilization." Wittgenstein said that of "the two interpretations of the Essence of the Good", that which holds that "the Good is good, in virtue of the fact that God wills it" is "the deeper", while that which holds that "God wills the good, because it is good" is "the shallow, rationalistic one, in that it behaves 'as though' that which is good could be given some further foundation". Today, divine command theory is defended by many philosophers of religion, though typically in a restricted form (see below).

Criticisms

This horn of the dilemma also faces several problems:

  • No reasons for morality: If there is no moral standard other than God's will, then God's commands are arbitrary (i.e., based on pure whimsy or caprice). This would mean that morality is ultimately not based on reasons: "if theological voluntarism is true, then God's commands/intentions must be arbitrary; [but] it cannot be that morality could wholly depend on something arbitrary... [for] when we say that some moral state of affairs obtains, we take it that there is a reason for that moral state of affairs obtaining rather than another." And as Michael J. Murray and Michael Rea put it, this would also "cas[t] doubt on the notion that morality is genuinely objective." An additional problem is that it is difficult to explain how true moral actions can exist if one acts only out of fear of God or in an attempt to be rewarded by him.
  • No reasons for God: This arbitrariness would also jeopardize God's status as a wise and rational being, one who always acts on good reasons. As Leibniz writes: "Where will be his justice and his wisdom if he has only a certain despotic power, if arbitrary will takes the place of reasonableness, and if in accord with the definition of tyrants, justice consists in that which is pleasing to the most powerful? Besides it seems that every act of willing supposes some reason for the willing and this reason, of course, must precede the act."
  • Anything goes: This arbitrariness would also mean that anything could become good, and anything could become bad, merely upon God's command. Thus if God commanded us "to gratuitously inflict pain on each other" or to engage in "cruelty for its own sake" or to hold an "annual sacrifice of randomly selected ten-year-olds in a particularly gruesome ritual that involves excruciating and prolonged suffering for its victims", then we would be morally obligated to do so. As 17th-century philosopher Ralph Cudworth put it: "nothing can be imagined so grossly wicked, or so foully unjust or dishonest, but if it were supposed to be commanded by this omnipotent Deity, must needs upon that hypothesis forthwith become holy, just, and righteous."
  • Moral contingency: If morality depends on the perfectly free will of God, morality would lose its necessity: "If nothing prevents God from loving things that are different from what God actually loves, then goodness can change from world to world or time to time. This is obviously objectionable to those who believe that claims about morality are, if true, necessarily true." In other words, no action is necessarily moral: any right action could have easily been wrong, if God had so decided, and an action which is right today could easily become wrong tomorrow, if God so decides. Indeed, some have argued that divine command theory is incompatible with ordinary conceptions of moral supervenience.
  • Why do God's commands obligate?: Mere commands do not create obligations unless the commander has some commanding authority. But this commanding authority cannot itself be based on those very commands (i.e., a command to obey commands), otherwise a vicious circle results. So, in order for God's commands to obligate us, he must derive commanding authority from some source other than his own will. As Cudworth put it: "For it was never heard of, that any one founded all his authority of commanding others, and others [sic] obligation or duty to obey his commands, in a law of his own making, that men should be required, obliged, or bound to obey him. Wherefore since the thing willed in all laws is not that men should be bound or obliged to obey; this thing cannot be the product of the meer [sic] will of the commander, but it must proceed from something else; namely, the right or authority of the commander." To avoid the circle, one might say our obligation comes from gratitude to God for creating us. But this presupposes some sort of independent moral standard obligating us to be grateful to our benefactors. As 18th-century philosopher Francis Hutcheson writes: "Is the Reason exciting to concur with the Deity this, 'The Deity is our Benefactor?' Then what Reason excites to concur with Benefactors?" Or finally, one might resort to Hobbes's view: "The right of nature whereby God reigneth over men, and punisheth those that break his laws, is to be derived, not from his creating them (as if he required obedience, as of gratitude for his benefits), but from his irresistible power." In other words, might makes right.
  • God's goodness: If all goodness is a matter of God's will, then what shall become of God's goodness? Thus William P. Alston writes, "since the standards of moral goodness are set by divine commands, to say that God is morally good is just to say that he obeys his own commands... that God practises what he preaches, whatever that might be;" Hutcheson deems such a view "an insignificant tautology, amounting to no more than this, 'That God wills what he wills.'" Alternatively, as Leibniz puts it, divine command theorists "deprive God of the designation good: for what cause could one have to praise him for what he does, if in doing something quite different he would have done equally well?" A related point is raised by C. S. Lewis: "if good is to be defined as what God commands, then the goodness of God Himself is emptied of meaning and the commands of an omnipotent fiend would have the same claim on us as those of the 'righteous Lord.'" Or again Leibniz: "this opinion would hardly distinguish God from the devil." That is, since divine command theory trivializes God's goodness, it is incapable of explaining the difference between God and an all-powerful demon.
  • The is-ought problem and the naturalistic fallacy: According to David Hume, it is hard to see how moral propositions featuring the relation ought could ever be deduced from ordinary is propositions, such as "the being of a God." Divine command theory is thus guilty of deducing moral oughts from ordinary ises about God's commands. In a similar vein, G. E. Moore argued (with his open question argument) that the notion good is indefinable, and any attempts to analyze it in naturalistic or metaphysical terms are guilty of the so-called "naturalistic fallacy." This would block any theory which analyzes morality in terms of God's will: and indeed, in a later discussion of divine command theory, Moore concluded that "when we assert any action to be right or wrong, we are not merely making an assertion about the attitude of mind towards it of any being or set of beings whatever."
  • No morality without God: If all morality is a matter of God's will, then if God does not exist, there is no morality. This is the thought captured in the slogan (often attributed to Dostoevsky) "If God does not exist, everything is permitted." Divine command theorists disagree over whether this is a problem for their view or a virtue of their view. Many argue that morality does indeed require God's existence, and that this is in fact a problem for atheism. But divine command theorist Robert Merrihew Adams contends that this idea ("that no actions would be ethically wrong if there were not a loving God") is one that "will seem (at least initially) implausible to many", and that his theory must "dispel [an] air of paradox."

Restricted divine command theory

One common response to the Euthyphro dilemma centers on a distinction between value and obligation. Obligation, which concerns rightness and wrongness (or what is required, forbidden, or permissible), is given a voluntarist treatment. But value, which concerns goodness and badness, is treated as independent of divine commands. The result is a restricted divine command theory that applies only to a specific region of morality: the deontic region of obligation. This response is found in Francisco Suárez's discussion of natural law and voluntarism in De legibus and has been prominent in contemporary philosophy of religion, appearing in the work of Robert M. Adams, Philip L. Quinn, and William P. Alston.

A significant attraction of such a view is that, since it allows for a non-voluntarist treatment of goodness and badness, and therefore of God's own moral attributes, some of the aforementioned problems with voluntarism can perhaps be answered. God's commands are not arbitrary: there are reasons which guide his commands based ultimately on this goodness and badness. God could not issue horrible commands: God's own essential goodness or loving character would keep him from issuing any unsuitable commands. Our obligation to obey God's commands does not result in circular reasoning; it might instead be based on a gratitude whose appropriateness is itself independent of divine commands. These proposed solutions are controversial, and some steer the view back into problems associated with the first horn.

One problem remains for such views: if God's own essential goodness does not depend on divine commands, then on what does it depend? Something other than God? Here the restricted divine command theory is commonly combined with a view reminiscent of Plato: God is identical to the ultimate standard for goodness. Alston offers the analogy of the standard meter bar in France. Something is a meter long inasmuch as it is the same length as the standard meter bar, and likewise, something is good inasmuch as it approximates God. If one asks why God is identified as the ultimate standard for goodness, Alston replies that this is "the end of the line," with no further explanation available, but adds that this is no more arbitrary than a view that invokes a fundamental moral standard. On this view, then, even though goodness is independent of God's will, it still depends on God, and thus God's sovereignty remains intact.

This solution has been criticized by Wes Morriston. If we identify the ultimate standard for goodness with God's nature, then it seems we are identifying it with certain properties of God (e.g., being loving, being just). If so, then the dilemma resurfaces: is God good because he has those properties, or are those properties good because God has them? Nevertheless, Morriston concludes that the appeal to God's essential goodness is the divine-command theorist's best bet. To produce a satisfying result, however, it would have to give an account of God's goodness that does not trivialize it and does not make God subject to an independent standard of goodness.

Moral philosopher Peter Singer, disputing the perspective that "God is good" and could never advocate something like torture, states that those who propose this are "caught in a trap of their own making, for what can they possibly mean by the assertion that God is good? That God is approved of by God?"

False dilemma in classical theistic perspective

Augustine, Anselm, and Aquinas all wrote about the issues raised by the Euthyphro dilemma, although, like William James and Wittgenstein later, they did not mention it by name. As philosopher and Anselm scholar Katherin A. Rogers observes, many contemporary philosophers of religion suppose that there are true propositions which exist as platonic abstracta independently of God. Among these are propositions constituting a moral order, to which God must conform in order to be good. Classical Judaeo-Christian theism, however, rejects such a view as inconsistent with God's omnipotence, which requires that God and what he has made is all that there is. "The classical tradition," Rogers notes, "also steers clear of the other horn of the Euthyphro dilemma, divine command theory." From a classical theistic perspective, therefore, the Euthyphro dilemma is false. As Rogers puts it, "Anselm, like Augustine before him and Aquinas later, rejects both horns of the Euthyphro dilemma. God neither conforms to nor invents the moral order. Rather His very nature is the standard for value." Another criticism raised by Peter Geach is that the dilemma implies you must search for a definition that fits piety rather than work backwards by deciding pious acts (i.e. you must know what piety is before you can list acts which are pious). It also implies something can not be pious if it is only intended to serve the Gods without actually fulfilling any useful purpose.

Jewish thought

The basis of the false dilemma response—God's nature is the standard for value—predates the dilemma itself, appearing first in the thought of the eighth-century BC Hebrew prophets, Amos, Hosea, Micah and Isaiah. (Amos lived some three centuries before Socrates and two before Thales, traditionally regarded as the first Greek philosopher.) "Their message," writes British scholar Norman H. Snaith, "is recognized by all as marking a considerable advance on all previous ideas," not least in its "special consideration for the poor and down-trodden." As Snaith observes, tsedeq, the Hebrew word for righteousness, "actually stands for the establishment of God's will in the land." This includes justice, but goes beyond it, "because God's will is wider than justice. He has a particular regard for the helpless ones on earth." Tsedeq "is the norm by which all must be judged" and it "depends entirely upon the Nature of God."

Hebrew has few abstract nouns. What the Greeks thought of as ideas or abstractions, the Hebrews thought of as activities. In contrast to the Greek dikaiosune (justice) of the philosophers, tsedeq is not an idea abstracted from this world of affairs. As Snaith writes:

Tsedeq is something that happens here, and can be seen, and recognized, and known. It follows, therefore, that when the Hebrew thought of tsedeq (righteousness), he did not think of Righteousness in general, or of Righteousness as an Idea. On the contrary, he thought of a particular righteous act, an action, concrete, capable of exact description, fixed in time and space.... If the word had anything like a general meaning for him, then it was as it was represented by a whole series of events, the sum-total of a number of particular happenings.

The Hebrew stance on what came to be called the problem of universals, as on much else, was very different from that of Plato and precluded anything like the Euthyphro dilemma. This has not changed. In 2005, Jonathan Sacks wrote, "In Judaism, the Euthyphro dilemma does not exist." Jewish philosophers Avi Sagi and Daniel Statman criticized the Euthyphro dilemma as "misleading" because "it is not exhaustive": it leaves out a third option, namely that God "acts only out of His nature."

St. Thomas Aquinas

Like Aristotle, Aquinas rejected Platonism. In his view, to speak of abstractions not only as existent, but as more perfect exemplars than fully designated particulars, is to put a premium on generality and vagueness. On this analysis, the abstract "good" in the first horn of the Euthyphro dilemma is an unnecessary obfuscation. Aquinas frequently quoted with approval Aristotle's definition, "Good is what all desire." As he clarified, "When we say that good is what all desire, it is not to be understood that every kind of good thing is desired by all, but that whatever is desired has the nature of good." In other words, even those who desire evil desire it "only under the aspect of good," i.e., of what is desirable. The difference between desiring good and desiring evil is that in the former, will and reason are in harmony, whereas in the latter, they are in discord.

Aquinas's discussion of sin provides a good point of entry to his philosophical explanation of why the nature of God is the standard for value. "Every sin," he writes, "consists in the longing for a passing [i.e., ultimately unreal or false] good." Thus, "in a certain sense it is true what Socrates says, namely that no one sins with full knowledge." "No sin in the will happens without an ignorance of the understanding." God, however, has full knowledge (omniscience) and therefore by definition (that of Socrates, Plato, and Aristotle as well as Aquinas) can never will anything other than what is good. It has been claimed – for instance, by Nicolai Hartmann, who wrote: "There is no freedom for the good that would not be at the same time freedom for evil" – that this would limit God's freedom, and therefore his omnipotence. Josef Pieper, however, replies that such arguments rest upon an impermissibly anthropomorphic conception of God. In the case of humans, as Aquinas says, to be able to sin is indeed a consequence, or even a sign, of freedom (quodam libertatis signum). Humans, in other words, are not puppets manipulated by God so that they always do what is right. However, "it does not belong to the essence of the free will to be able to decide for evil." "To will evil is neither freedom nor a part of freedom." It is precisely humans' creatureliness – that is, their not being God and therefore omniscient – that makes them capable of sinning. Consequently, writes Pieper, "the inability to sin should be looked on as the very signature of a higher freedom – contrary to the usual way of conceiving the issue." Pieper concludes: "Only the will [i.e., God's] can be the right standard of its own willing and must will what is right necessarily, from within itself, and always. A deviation from the norm would not even be thinkable. And obviously only the absolute divine will is the right standard of its own act" – and consequently of all human acts. Thus the second horn of the Euthyphro dilemma, divine command theory, is also disposed of.

Thomist philosopher Edward Feser writes, "Divine simplicity [entails] that God's will just is God's goodness which just is His immutable and necessary existence. That means that what is objectively good and what God wills for us as morally obligatory are really the same thing considered under different descriptions, and that neither could have been other than they are. There can be no question then, either of God's having arbitrarily commanded something different for us (torturing babies for fun, or whatever) or of there being a standard of goodness apart from Him. Again, the Euthyphro dilemma is a false one; the third option that it fails to consider is that what is morally obligatory is what God commands in accordance with a non-arbitrary and unchanging standard of goodness that is not independent of Him... He is not under the moral law precisely because He is the moral law."

William James

William James, in his essay "The Moral Philosopher and the Moral Life", dismisses the first horn of the Euthyphro dilemma and stays clear of the second. He writes: "Our ordinary attitude of regarding ourselves as subject to an overarching system of moral relations, true 'in themselves,' is ... either an out-and-out superstition, or else it must be treated as a merely provisional abstraction from that real Thinker ... to whom the existence of the universe is due." Moral obligations are created by "personal demands," whether these demands come from the weakest creatures, from the most insignificant persons, or from God. It follows that "ethics have as genuine a foothold in a universe where the highest consciousness is human, as in a universe where there is a God as well." However, whether "the purely human system" works "as well as the other is a different question."

For James, the deepest practical difference in the moral life is between what he calls "the easy-going and the strenuous mood." In a purely human moral system, it is hard to rise above the easy-going mood, since the thinker's "various ideals, known to him to be mere preferences of his own, are too nearly of the same denominational value; he can play fast and loose with them at will. This too is why, in a merely human world without a God, the appeal to our moral energy falls short of its maximum stimulating power." Our attitude is "entirely different" in a world where there are none but "finite demanders" from that in a world where there is also "an infinite demander." This is because "the stable and systematic moral universe for which the ethical philosopher asks is fully possible only in a world where there is a divine thinker with all-enveloping demands", for in that case, "actualized in his thought already must be that ethical philosophy which we seek as the pattern which our own must evermore approach." Even though "exactly what the thought of this infinite thinker may be is hidden from us", our postulation of him serves "to let loose in us the strenuous mood" and confront us with an existential "challenge" in which "our total character and personal genius ... are on trial; and if we invoke any so-called philosophy, our choice and use of that also are but revelations of our personal aptitude or incapacity for moral life. From this unsparing practical ordeal no professor's lectures and no array of books can save us." In the words of Richard M. Gale, "God inspires us to lead the morally strenuous life in virtue of our conceiving of him as unsurpassably good. This supplies James with an adequate answer to the underlying question of the Euthyphro."

In philosophical atheism

Atheistic resolutions

Atheism challenges the assumption of the dilemma that God exists (or in the original formulation, that the many gods in Greek religion existed). This eliminates the need to decide whether God is either non-omniscient or arbitrary, and also eliminates the possibility of God as the source of morality.

Secular humanism takes the positive stance that morality is not dependent on religion or theology, and that ethical rules should be developed based on reason, science, experience, debate, and democracy. Some secular humanists believe in ethical naturalism, that there are objective, discoverable laws of morality inherent to the human condition, of which humans may have imperfect knowledge. Others have adopted ethical subjectivism in the sense of meta-ethics – the idea that ethics are a social construct – but nonetheless by way of utilitarianism advocate imposing a set of universal ethics and laws that create the type of society in which they wish to live, where people are safe, prosperous, and happy. These competing resolutions represent different answers to a question similar to the original dilemma: "Is something inherently ethical or unethical, or is something ethical or unethical because a person or society says it is so?"

Rejection of universal morality

The other assumption of the dilemma is that there is a universal right and wrong, against which a god either creates or is defined by. Moral nihilism challenges that assumption by rejecting the concept of morality entirely. This conflicts with the teachings of most religions (and thus is usually accompanied by atheism) but is theoretically compatible with the notion of a powerful God or gods who have opinions about how people should behave.

Alexander Rosenberg uses a version of the Euthyphro dilemma to argue that objective morality cannot exist and hence an acceptance of moral nihilism is warranted. He asks, is objective morality correct because evolution discovered it or did evolution discover objective morality because it is correct? If the first horn of the dilemma is true then our current morality cannot be objectively correct by accident because if evolution had given us another type of morality then that would have been objectively correct. If the second horn of dilemma is true then one must account for how the random process of evolution managed to only select for objectively correct moral traits while ignoring the wrong moral traits. Given the knowledge that evolution has given us tendencies to be xenophobic and sexist it is mistaken to claim that evolution has only selected for objective morality as evidently it did not. Because both horns of the dilemma do not give an adequate account for how the evolutionary process instantiated objective morality in humans, a position of Moral nihilism is warranted.

Moral relativism accepts the idea of morality, but asserts that there are multiple potential arbiters of moral truth. This opens the possibility of disagreeing with God about the rules of ethics, and of creating multiple societies with different, equally valid sets of ethics (just as different countries have different sets of laws). "Normative moral relativism" asserts that behavior based on alternative systems of morality should be tolerated. In the context of religious pluralism, strong relativism it also opens the possibility that different gods and different belief systems produce different but equally valid moral systems, which may apply only to adherents of those faiths.

In popular culture

In the song "No Church in the Wild" from the album Watch the Throne, rapper Jay Z references the dilemma with the line, "Is pious pious 'cause God loves pious? Socrates asked whose bias do y'all seek."

In American legal thinking

Yale Law School Professor Myres S. McDougal, formerly a classicist, later a scholar of property law, posed the question, "Do we protect it because it's a property right, or is it a property right because we protect it?" The dilemma has also been restated in legal terms by Geoffrey Hodgson, who asked: "Does a state make a law because it is a customary rule, or does law become a customary rule because it is approved by the state?"

Mindset

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Mindset

Mindset is an "established set of attitudes, esp. regarded as typical of a particular group's social or cultural values; the outlook, philosophy, or values of a person; (now also more generally) frame of mind, attitude, [recte: and] disposition." A mindset may also arise from a person's world view or philosophy of life.

A firmly established mindset could create a powerful incentive to adopt or accept prior behaviors, choices, or tools, sometimes referred to as cognitive inertia, or "groupthink." Within these phenomena, it is often difficult to counteract its effects upon analysis and decision making processes.

In cognitive psychology, a mindset represents the cognitive processes activated in response to a given task (French, 2016). According to French and Chang (2016), scholarly conceptualizations of mindset shift "to the varied definitions and conceptualizations" which "demarcates this literature via a novel categorization using the construct of mindset."

History of research

Some of the earliest empirical explorations of mindset originated in the 1900s with the work of psychology professor Peter M. Gollwitzer. These studies are identified as foundational and precursory for the study of cognition (Gollwitzer 1990, 2012). Gollwitzer's most notable contributions include his theory of mindset and the mindset theory of action phases (French, 2016).

In addition to the field of cognitive psychology, the study of mindset is evident within the social sciences and several other fields (e.g., positive psychology). A characteristic of this area of study, in various manifestations, is the fragment use of mindset throughout the academy (e.g. French, 2016).

In politics

A political example is the "Cold War mindset" prevalent in both the U.S. and USSR, which included absolute trust in two-player game theory, in the integrity of command chain, in control of nuclear materials, and in the mutual assured destruction of both in the case of war. This mindset usefully served to prevent an attack by either country; however, the assumptions underlying deterrence theory have made assessments of the efficacy of the Cold War mindset a matter of some controversy.

Most theorists consider that the key responsibility of an embedded power group is to challenge the assumptions that comprise the group's own mindset. According to these commentators, power groups that fail to review or revise their mindsets with sufficient regularity cannot hold power indefinitely, as a single mindset is unlikely to possess the flexibility and adaptability needed to address all future events. For example, the variations in mindset between Democratic Party and Republican Party presidents in the U.S. may have made that country more able to challenge assumptions than the Kremlin with its more static bureaucracy.

Modern military theory attempts to challenge entrenched mindsets in dealing with asymmetric warfare, terrorism, and the proliferation of weapons of mass destruction. In combination, these threats represent "a revolution in military affairs" and require very rapid adaptation to new threats and circumstances.[7] In this context, the cost of not implementing adaptive mindsets cannot be afforded.

In system thinking

Building on Magoroh Maruyama's concept of Mindscape, Mindset Theory includes cultural and social orientation type values: Hierarchical Individualism (HI), Egalitarian Individualism (EI), Hierarchical Collectivism (HC), Egalitarian Collectivism (EC), Hierarchic Synergism (HS), Egalitarian Synergism (ES), Hierarchical Populism (HP), and Egalitarian Populism (EP).

Collective

Collective mindsets are described in Hutchin's "Cognition in the Wild" (1995) or Senges' "Knowledge entrepreneurship in universities" (2007). Hutchin analyzes a team of naval navigators as the cognitive unit or as a computational system, while Senges discusses the usefulness and functionality entrepreneurship concept by explaining how the concept is identified in the strategy and practice of universities (Senges, 2007).

There are also parallels to the emerging field of "collective intelligence" (e.g. (Zara, 2004)) and exploiting the "Wisdom of the crowds" (Surowiecki, 2005) of stakeholders. Zara notes that since collective reflection is more explicit, discursive, and conversational, it therefore needs a good ¿gestell?—especially when it comes to information and communication technology.

Erik H. Erikson's (1974) analysis of group-identities and what he calls a "life-plan" is relevant to the embodiment of a collective mindset. He recounts the example of American Indians, who were meant to undergo a reeducation process to instill a modern "life-plan" that aimed for housing and wealth. Erikson writes that the Indians' collective historic identity as buffalo hunters was oriented around such fundamentally different motivations that even communication about divergent "life plans" was difficult (Erikson, 1974).

There is a double relation between the institution embodying collective mindset. One example is the entrepreneurial mindset which refers to a person who "values uncertainty in the marketplace and seeks to continuously identify opportunities with the potential to lead to important innovations" (Hitt, 2011, pg. 371). An institution with an entrepreneurial philosophy will set entrepreneurial goals and strategies as a whole, but maybe even more importantly, it will foster an entrepreneurial milieu, allowing each entity to pursue emergent opportunities. A philosophical stance codified in the mind, as mindset, will lead to a climate that in turn causes values that lead to practice. Hitt's novel cites five dimensions of entrepreneurial mindset as "autonomy, innovativeness, risk taking, proactiveness, and competitive aggressiveness" (Hitt, 2011, pg. 354).

Specific theories

Types and theories

Variation within the study of mindsets includes how to define, measure, and conceptualize a mindset as well as the types of mindset identified. Substantial variations exist even among scholars within the same discipline, studying the same mindset (French, 2016). Nevertheless, any discussion of mindset should include recognition concerning the numerous, varied, and growing number of mindsets and mindset theories that receive attention in multiple disciplines throughout academia.

Mindset agency theory

Mindset theory, as based on the cultural values defined by Sagiv and Schwarts, explains the nature, functions, and variables that make up the characteristics of personality. The mindscape theory and cultural values outlined by Sagive and Schwarts combine to make a more comprehensive whole of mindset agency theory.

Mindscape theory

The Myer's–Briggs Type Indicator (MBTI) deals with psychological functions that, paired with values of social attitude, combine in certain ways to generate personality patterns called "types" that may be evaluated by exploring individual preferences (which change with context). Different is Maruyama's mindscape theory which works with epistemological types. Mindscapes seek to measure individuals on a scale of characteristics and place them into four categories of personalities that make up the population of the world. Each category contains differing views toward information, perception, logic, and ethics. Hierarchical Bureaucrats generally view the world as having natural order with competition and consequences much like natural selection. Independent Princes view the world as random, individualistic, and chaotic with a natural decay that is inevitable. Social Reformers view the world as a balance that can be maintained by symbiosis between everything. Generative Revolutionaries view the world as potential for growth through interaction and symbiosis; change is encouraged.

Sagiv-Schwarts cultural values

Sagiv and Schwarts posited three bi-polar dimensions to culture based on values. These dimensions contain opposites in the realms of cognitive, figurative, and operative values:

  • Cognitive: embeddedness or autonomy
  • Figurative: mastery or harmony
  • Operative: hierarchy or egalitarian

Fixed and growth mindset

According to Carol Dweck, individuals can be placed on a continuum according to their implicit views of "where ability comes from". The two categorical extremes are fixed mindsets and growth mindsets. In particular, an individual's mindset impacts "motivation to practice and learn". A growth mindset is seen as more positive and helpful, with most research focusing on how to develop this mindset.

Fixed Mindset

Those with a fixed mindset believe "intelligence is static" and there is very little to be done to improve ability. Feedback is seen as an "evaluation of their underlying ability" since success is seen only as a result of this innate ability, not the effort put in. Failure is much more intimidating since it "suggests constraints or limits they would not be able to overcome". Those with a fixed mindset tend to avoid challenges, give up easily, and focus on the outcome. They believe that their talents and abilities are a fixed trait that they are either born with or not born with; thus, effort is not valued as worthwhile to the fixed mindset individual.

Growth Mindset

Those with a growth mindset believe "intelligence can be developed" and their abilities can be enhanced through the learning process. With a growth mindset, individuals tend to embrace challenges, persevere in the face of adversity, accept and learn from failure, and focus on the process rather than the outcome. They see talents and abilities as skills that are developed through effort. Feedback and failure are seen as opportunities for increasing ability signaling the "need to pay attention, invest effort, apply time to practice, and master the new learning opportunity".

Grit closely relates to a growth mindset. Grit can be defined as the combination of determination and perseverance. Keown and Bourke discussed the importance for those growing up to have a combination of not only a growth mindset but also grit. Their 2019 study found that those in a lower economic status had a higher chance of success if they had a growth mindset and were willing to work hard through tribulation.

Classroom Implications

A large part of Dweck's research on mindsets was conducted in the field of education. This research was related to how mindsets affect a student's performance in the classroom. In order for students to effectively adopt a growth mindset, a classroom culture needs to be established that nurtures this type of thinking. One of the ways educators can do this is by creating a growth-mindset culture in their classroom that provides the right kind of praise and encouragement. According to Dweck (2010), "praising students for the process they have engaged in—the effort they applied, the strategies they used, the choices they made, the persistence they displayed, and so on—yields more long-term benefits than telling them they are 'smart' when they succeed". As such, it is important for educators to carefully craft and design meaningful learning activities for their students to engage in the classroom. Dweck (2010) states, "the teacher should portray challenges as fun and exciting, while portraying easy tasks as boring and less useful for the brain". Students who are engaged in more challenging learning activities have more opportunities to make mistakes and struggle, allowing the teacher to interject with new strategies to try while praising students for the work they have done so far.

A second strategy to promote a growth-mindset culture in the classroom is to explicitly teach lessons related to what it means to adopt a growth mindset. Possible activities include establishing personal goals and writing letters. Another practice for promoting growth mindset includes having students "write about and share with one another something they used to be poor at and now are very good at." An additional study by Hinda Hussein (2018), examined the effects of reflective journal writing on students' growth mindset. Findings indicated journaling could positively affect a student's learning process by improving their conceptual knowledge, promoting growth mindset, and enhancing understanding of their thoughts through writing.

The way educators evaluate their students' work and communicate their progress can also contribute to the establishment of a growth mindset culture in the classroom. Dweck (2010) identifies the word "yet" as a valuable tool to assess students' learning. If an educator hears students saying they are not good at something or can't do something, it is important for the teacher to interject with the words "not yet" to reinforce the idea that ability and motivation are fluid. Overall, a classroom that includes challenging learning tasks, praising of the process, and explicit growth mindset teaching and assessment, is a classroom where students will have the tools needed to become lifelong learners.

Reshaping mindsets in students and educators

While elements of personality – such as sensitivity to mistakes and setbacks – can make us predisposed toward holding a certain mindset, we are able to develop and reshape our mindset through our interactions. In multiple studies, Dweck and her colleagues noted that alterations in mindset could be achieved through "praising the process through which success was achieved", "having [college aged students] read compelling scientific articles that support one view or the other", or teaching junior high school students "that every time they try hard and learn something new, their brain forms new connections that, over time, make them smarter." These studies demonstrate how framing and discussing students' work and effort plays a considerable role in the type of mindset students develop and students' conceptions of their own ability.

While much of the research in the field of education focuses on a student's ability to adopt a growth mindset, less attention and focus are given to teachers' mindsets and the role they play in influencing their students. Hattie (2012) states, "differing mindsets, or assumptions, that teachers possess about themselves and their students play a significant role in determining their expectations, teaching practices, and how students perceive their own mindset."

A study by Patrick & Joshi (2019) explored the way teachers explain growth and fixed mindsets. Using 150 semi-structured interviews, two major findings were revealed. First, they found that teachers' prior beliefs about learning and learners influenced how they engaged with these mindsets. Secondly, they found that many teachers tended to oversimplify the concepts of a growth and fixed mindset into positive and negative traits. These findings suggest a need for more teacher training and support for teachers to successfully implement growth mindset initiatives in their classrooms.

An additional study conducted by Fiona S. Seaton (2018), looked specifically at the impact of teacher training aimed at influencing their mindsets and the effect on their resulting practice. The teachers in this study underwent six different training sessions. Seaton found that the training sessions had an impact on teachers' mindsets and that this change was sustained three months after the training. The results of this study suggest that adults' mindsets are malleable and can shift if the right supports are in place. This study also reinforces the bond between a teacher's own beliefs and how they can strongly influence the mindset of their students; therefore, further highlighting the need for proper teacher training in order for mindset initiatives within schools to be fully successful.

Fixed and growth mindsets in males vs. females

Carol Dweck and Jo Boaler have done extensive research on the topics of fixed and growth mindset, which indicates an existing disparity in the fixed and growth mindsets of females and males. Boaler's 2013 article "Ability and Mathematics: the Mindset Revolution that is Reshaping Education," argues that fixed mindset beliefs lead to inequalities in education which partially explains low achievement and participation amongst minorities and female students. Boaler builds on Carol Dweck's research to show that "gender differences in mathematics performance only existed among fixed mindset students" (Boaler, 2013).

Boaler and Dweck argue that people with growth mindsets can gain knowledge. Boaler said, "The key growth mindset message was that effort changes the brain by forming new connections, and that students control this process. The growth mindset intervention halted the students' decline in grades and started the students on a new pathway of improvement and high achievement" (Boaler, 2013, pg. 5). Educational systems focusing on creating a growth mindset environment allow girls to feel like their intelligence is malleable rather than constant.

In addition, L.S. Blackwell (2015) delivered research exploring if growth mindsets can be promoted within minority groups. Blackwell also builds on Dweck's research to observe minority groups and found that "students with a growth mindset had stronger learning goals than the fixed mindset students." These students also "had much more positive attitudes toward effort, agreeing that “when something is hard, it just makes me want to work more on it, not less.” Students with a fixed mindset, on the other hand, were more likely to say that “If you’re not good at a subject, working hard won’t make you good at it,” and “When I work hard at something, it makes me feel like I’m not very smart.” (Blackwell, 2015).

Implications for at risk students

Dweck's research on the theory of growth and fixed mindsets is useful in intervention strategies with at risk students, dispelling negative stereotypes in education held by teachers and students, understanding the impacts of self-theories on resilience, and understanding how process praise can foster a growth mindset and positively impact students' motivation levels. Other scholars have conducted further research building on Dweck's findings. In particular, a study by Rhew et al. (2018) suggested that a growth mindset intervention can increase the motivation levels of adolescent special education participants. Another study by Wang et al. (2019) suggested that substance use has adverse effects on adolescent reasoning. Developing a growth mindset in these adolescents was shown to reduce this adverse effect.

These studies further illustrate how educators can use intervention strategies, targeting a growth mindset, by allowing students to see that their behavior can be changed with effort.

Criticism

In recent years, criticism has been directed at "growth mindset" as a concept, and related research. Moreau et al. (2019) suggest "that overemphasizing the malleability of abilities and other traits can have negative consequences for individuals, science, and society."

Benefit mindset

In 2015, Ashley Buchanan and Margaret L. Kern proposed a complementary evolution to the fixed and growth mindset called the benefit mindset. The benefit mindset describes society's everyday leaders who promote well-being on both an individual and a collective level. That is, people who discover their strengths to make valuable contributions to causes that are greater than the self. They question why they do what they do, positioning their actions within a purposeful context.

Buchanan and Kern argue "creating cultures of contribution and everyday leadership could be one of the best points of leverage we have for simultaneously bringing out the best in people, organizations and the planet."

Global mindset

Originating from the study of organizational leadership and coinciding with the growth of multinational corporations in the 1980s, organizations observed that the effectiveness of their executives did not necessarily translate cross-culturally. Global mindset emerged as an explanation (Javidan & Walker, 2013). Leaders in cross-cultural contexts were hypothesized to need an additional skill, ability, or proficiency (i.e. a global mindset) to enable effectiveness regardless of the culture or context (Perlmutter, 1969; Rhinesmith, 1992). Cultural agility refers to the changes implied in such need.

One of the defining characteristics of the study of global mindset is the variety in which scholars conceptualize and operationalize the construct. Yet, scholars typically agree that global mindset and its development increase global effectiveness for both individuals and organizations (French & Chang, 2016).

Abundance and scarcity

Those with abundance mindset believe that there are enough resources for everyone, seeing the glass half full. While those with the scarcity mindset believe that there is a limited number of resources, seeing the glass half empty. Mehta and Zhu (2012) found that a "scarcity mindset makes people think beyond established functionalities to explore broadly for solutions, thereby heightening creativity. In contrast, an abundance mindset induces functional fixedness, thereby reducing creativity."

Productive and defensive

According to Chris Argyris (2004), there are two dominant mindsets in organizations: the productive mindset and the defensive mindset. The productive mindset is hinged in logic and focuses on the knowledge and its certifiable results. This is more of a decision-making mindset which is transparent and auditable (Argyris, 2004).

The defensive mindset is a closed mindset like fixed mindset and is self-protective as well as self-deceptive. This mindset does not look at the greater good but centers on saving the skin of the person holding this mindset. It is highly likely that truth, if perceived harmful for the person concerned, would be shut down. This may allow personal growth but no organizational growth or development (Argyris, 2004).

Heritability of autism

From Wikipedia, the free encyclopedia

The heritability of autism is the proportion of differences in expression of autism that can be explained by genetic variation; if the heritability of a condition is high, then the condition is considered to be primarily genetic. Autism has a strong genetic basis, although the genetics of autism are complex and it is unclear whether autism spectrum disorder (ASD) is explained more by multigene interactions or by rare mutations with major effects.

Early studies of twins estimated the heritability of autism to be more than 90%; in other words, that 90% of the differences between autistic and non-autistic individuals are due to genetic effects. This however may be an overestimate: new twin data and models with structural genetic variation are needed. When only one identical twin is autistic, the other often has learning or social disabilities. For adult siblings, the likelihood of having one or more features of the broader autism phenotype might be as high as 30%, much higher than the likelihood in controls.

Genetic linkage analysis has been inconclusive; many association analyses have had inadequate power. For each autistic individual, mutations in more than one gene may be implicated. Mutations in different sets of genes may be involved in different autistic individuals. There may be significant interactions among mutations in several genes, or between the environment and mutated genes. By identifying genetic markers inherited with autism in family studies, numerous candidate genes have been located, most of which encode proteins involved in neural development and function. However, for most of the candidate genes, the actual mutations that increase the likelihood for autism have not been identified. Typically, autism cannot be traced to a Mendelian (single-gene) mutation or to single chromosome abnormalities such as fragile X syndrome or 22q13 deletion syndrome.

Deletion (1), duplication (2) and inversion (3) are all chromosome abnormalities that have been implicated in autism.

The large number of autistic individuals with unaffected family members may result from copy number variations (CNVs)—spontaneous alterations in the genetic material during meiosis that delete or duplicate genetic material. Sporadic (non-inherited) cases have been examined to identify candidate genetic loci involved in autism. A substantial fraction of autism may be highly heritable but not inherited: that is, the mutation that causes the autism is not present in the parental genome.

Although the fraction of autism traceable to a genetic cause may grow to 30–40% as the resolution of array CGH improves, several results in this area have been described incautiously, possibly misleading the public into thinking that a large proportion of autism is caused by CNVs and is detectable via array CGH, or that detecting CNVs is tantamount to a genetic diagnosis. The Autism Genome Project database contains genetic linkage and CNV data that connect autism to genetic loci and suggest that every human chromosome may be involved. It may be that using autism-related subphenotypes instead of the diagnosis of autism per se may be more useful in identifying susceptible loci.

Twin studies

Twin studies are a helpful tool in determining the heritability of disorders and human traits in general. They involve determining concordance of characteristics between identical (monozygotic or MZ) twins and between fraternal (dizygotic or DZ) twins. Possible problems of twin studies are: (1) errors in diagnosis of monozygocity, and (2) the assumption that social environment sharing by DZ twins is equivalent to that of MZ twins.

A condition that is environmentally caused without genetic involvement would yield a concordance for MZ twins equal to the concordance found for DZ twins. In contrast, a condition that is completely genetic in origin would theoretically yield a concordance of 100% for MZ pairs and usually much less for DZ pairs depending on factors such as the number of genes involved and assortative mating.

An example of a condition that appears to have very little if any genetic influence is irritable bowel syndrome (IBS), with a concordance of 28% vs. 27% for MZ and DZ pairs respectively. An example of a human characteristics that is extremely heritable is eye color, with a concordance of 98% for MZ pairs and 7–49% for DZ pairs depending on age.

Identical twin studies put autism's heritability in a range between 36% and 95.7%, with concordance for a broader phenotype usually found at the higher end of the range. Autism concordance in siblings and fraternal twins is anywhere between 0 and 23.5%. This is more likely 2–4% for classic autism and 10–20% for a broader spectrum. Assuming a general-population prevalence of 0.1%, the risk of classic autism in siblings is 20- to 40-fold that of the general population.

Notable twin studies have attempted to shed light on the heritability of autism.

A small scale study in 1977 was the first of its kind to look into the heritability of autism. It involved 10 DZ twins and 11 MZ twins in which at least one twin in each pair showed infantile autism. It found a concordance of 36% in MZ twins compared to 0% for DZ twins. Concordance of "cognitive abnormalities" was 82% in MZ pairs and 10% for DZ pairs. In 12 of the 17 pairs discordant for autism, a biological hazard was believed to be associated with the condition.

A 1979 case report discussed a pair of identical twins concordant for autism. The twins developed similarly until the age of 4, when one of them spontaneously improved. The other twin, who had had infrequent seizures, remained autistic. The report noted that genetic factors were not "all important" in the development of twins.

In 1985, a study of twins enrolled with the UCLA Registry for Genetic Studies found a concordance of 95.7% for autism in 23 pairs of MZ twins, and 23.5% for 17 DZ twins.

In a 1989 study, Nordic countries were screened for cases of autism. Eleven pairs of MZ twins and 10 of DZ twins were examined. Concordance of autism was found to be 91% in MZ and 0% in DZ pairs. The concordances for "cognitive disorder" were 91% and 30% respectively. In most of the pairs discordant for autism, the autistic twin had more perinatal stress.

A British twin sample was reexamined in 1995 and a 60% concordance was found for autism in MZ twins vs. 0% concordance for DZ. It also found 92% concordance for a broader spectrum in MZ vs. 10% for DZ. The study concluded that "obstetric hazards usually appear to be consequences of genetically influenced abnormal development, rather than independent aetiological factors."

A 1999 study looked at social cognitive skills in the general-population of children and adolescents. It found "poorer social cognition in males", and a heritability of 0.68 with higher genetic influence in younger twins.

In 2000, a study looked at reciprocal social behavior in general-population identical twins. It found a concordance of 73% for MZ, i.e. "highly heritable", and 37% for DZ pairs.

A 2004 study looked at 16 MZ twins and found a concordance of 43.75% for "strictly defined autism". Neuroanatomical differences (discordant cerebellar white and grey matter volumes) between discordant twins were found. The abstract notes that in previous studies 75% of the non-autistic twins displayed the broader phenotype.

Another 2004 study examined whether the characteristic symptoms of autism (impaired social interaction, communication deficits, and repetitive behaviors) show decreased variance of symptoms among monozygotic twins compared to siblings in a sample of 16 families. The study demonstrated significant aggregation of symptoms in twins. It also concluded that "the levels of clinical features seen in autism may be a result of mainly independent genetic traits."

An English twin study in 2006 found high heritability for autistic traits in a large group of 3,400 pairs of twins.

One critic of the pre-2006 twin studies said that they were too small and their results can be plausibly explained on non-genetic grounds.

Sibling studies

A study of 99 autistic probands which found a 2.9% concordance for autism in siblings, and between 12.4% and 20.4% concordance for a "lesser variant" of autism.

A study of 31 siblings of autistic children, 32 siblings of children with developmental delay, and 32 controls. It found that the siblings of autistic children, as a group, "showed superior spatial and verbal span, but a greater than expected number performed poorly on the set-shifting, planning, and verbal fluency tasks."

A 2005 Danish study looked at "data from the Danish Psychiatric Central Register and the Danish Civil Registration System to study some risk factors of autism, including place of birth, parental place of birth, parental age, family history of psychiatric disorders, and paternal identity." It found an overall prevalence rate of roughly 0.08%. Prevalence of autism in siblings of autistic children was found to be 1.76%. Prevalence of autism among siblings of children with Asperger syndrome or PDD was found to be 1.04%. The risk was twice as high if the mother had been diagnosed with a psychiatric disorder. The study also found that "the risk of autism was associated with increasing degree of urbanisation of the child's place of birth and with increasing paternal, but not maternal, age."

A study in 2007 looked at a database containing pedigrees of 86 families with two or more autistic children and found that 42 of the third-born male children showed autistic symptoms, suggesting that parents had a 50% chance of passing on a mutation to their offspring. The mathematical models suggest that about 50% of autistic cases are caused by spontaneous mutations. The simplest model was to divide parents into two risk classes depending on whether the parent carries a pre-existing mutation that causes autism; it suggested that about a quarter of autistic children have inherited a copy number variation from their parents.

Other family studies

A 1994 study looked at the personalities of parents of autistic children, using parents of children with Down syndrome as controls. Using standardized tests it was found that parents of autistic children were "more aloof, untactful and unresponsive" compared to parents whose children did not have autism.[34]

A 1997 study found higher rates of social and communication deficits and stereotyped behaviors in families with multiple-incidence autism.

Autism was found to occur more often in families of physicists, engineers and scientists. 12.5% of the fathers and 21.2% of the grandfathers (both paternal and maternal) of children with autism were engineers, compared to 5% of the fathers and 2.5% of the grandfathers of children with other syndromes. Other studies have yielded similar results. Findings of this nature have led to the coinage of the term "geek syndrome".

A 2001 study of brothers and parents of autistic boys looked into the phenotype in terms of one current cognitive theory of autism. The study raised the possibility that the broader autism phenotype may include a "cognitive style" (weak central coherence) that can confer information-processing advantages.

A study in 2005 showed a positive correlation between repetitive behaviors in autistic individuals and obsessive-compulsive behaviors in parents. Another 2005 study focused on sub-threshold autistic traits in the general population. It found that correlation for social impairment or competence between parents and their children and between spouses is about 0.4.

A 2005 report examined the family psychiatric history of 58 subjects with Asperger syndrome (AS) diagnosed according to DSM-IV criteria. Three (5%) had first-degree relatives with AS. Nine (19%) had a family history of schizophrenia. Thirty five (60%) had a family history of depression. Out of 64 siblings, 4 (6.25%) were diagnosed with AS. According to a 2022 study held on 86 mother-child dyads across 18 months, "prior maternal depression didn’t predict child behavior problems later."

Twinning risk

It has been suggested that the twinning process itself is a risk factor in the development of autism, presumably due to perinatal factors. However, three large-scale epidemiological studies have refuted this idea. These studies took place in California, Sweden, and Australia. One study done in Western Australia, utilized the Maternal and Child Health Research Database that houses birth records for all infants born, including infants and later children diagnosed with autism spectrum disorder. During this study, the population analyzed for the incidence of Autism Spectrum Disorder was restricted to those children with birth years between 1980 and 1995. The focus was on the incidence of autism spectrum disorder in the twin population in comparison to the non twin population. The following two studies, explored the risk of Autism spectrum disorder in the twin population. They drew the same conclusion was drawn that the twinning process alone is not a risk factor. In these studies the data exemplified that both MZ twins will have autism spectrum disorder, but only one of the DZ twins will have autism spectrum disorder with an incidence rate of 90% in MZ twins compared to 0% in DZ twins. The high symmetry in MZ twins can explain the high symmetry of autism spectrum disorder in MZ twins outcome compared to DZ twins and non twin siblings.

Proposed models

Twin and family studies show that autism is a highly heritable condition, but they have left many questions for researchers, most notably

  • Why is fraternal twin concordance so low considering that identical twin concordance is high?
  • Why are parents of autistic children typically non-autistic?
  • Which factors could be involved in the failure to find a 100% concordance in identical twins?
  • Is profound intellectual disability a characteristic of the genotype or something totally independent?

Clues to the first two questions come from studies that have shown that at least 30% of individuals with autism have spontaneous de novo mutations that occurred in the father's sperm or mother's egg that disrupts important genes for brain development, these spontaneous mutations are likely cause autism in families where there is no family history. The concordance between identical twins isn't quite 100% for two reasons, because these mutations have variable 'expressivity' and their effects manifest differently due to chance effects, epigenetic, and environmental factors. Also spontaneous mutations can potentially occur specifically in one embryo and not the other after conception. The likelihood of developing intellectual disability is dependent on the importance of the gene to brain development and how the mutation changes this function, also playing a role is the genetic and environmental background upon which a mutation occurs. The recurrence of the same mutations in multiple individuals affected by autism has led Brandler and Sebat to suggest that the spectrum of autism is breaking up into quanta of many different genetic disorders.

Single genes

The most parsimonious explanation for cases of autism where a single child is affected and there is no family history or affected siblings is that a single spontaneous mutation that impacts one or multiple genes is a significant contributing factor. Tens of individual genes or mutations have been definitively identified and are cataloged by the Simons Foundation Autism Research Initiative. Examples of autism that has arisen from a rare or de novo mutation in a single-gene or locus include the neurodevelopmental disorders fragile X syndrome, 22q13 deletion syndrome, and 16p11.2 deletion syndrome.

These mutations themselves are characterized by considerable variability in clinical outcome and typically only a subset of mutation carriers meet criteria for autism. For example, carriers of the 16p11.2 deletion have a mean IQ 32 points lower than their first-degree relatives that do not carry the deletion, however only 20% are below the threshold IQ of 70 for intellectual disability, and only 20% have autism. Around 85% have a neurobehavioral diagnosis, including autism, ADHD, anxiety disorders, mood disorders, gross motor delay, and epilepsy, while 15% have no diagnosis. Alongside these neurobehavioral phenotypes, the 16p11.2 deletions / duplications have been associated with macrocephaly / microcephaly, body weight regulation, and the duplication in particular is associated with schizophrenia. Controls that carry mutations associated with autism or schizophrenia typically present with intermediate cognitive phenotypes or fecundity compared to neurodevelopmental cases and population controls. Therefore, a single mutation can have multiple different effects depending on other genetic and environmental factors.

Multigene interactions

In this model, autism often arises from a combination of common, functional variants of genes. Each gene contributes a relatively small effect in increasing the risk of autism. In this model, no single gene directly regulates any core symptom of autism such as social behavior. Instead, each gene encodes a protein that disrupts a cellular process, and the combination of these disruptions, possibly together with environmental influences, affect key developmental processes such as synapse formation. For example, one model is that many mutations affect MET and other receptor tyrosine kinases, which in turn converge on disruption of ERK and PI3K signaling.

Two family types

In this model most families fall into two types: in the majority, sons have a low risk of autism, but in a small minority their risk is near 50%. In the low-risk families, sporadic autism is mainly caused by spontaneous mutation with poor penetrance in daughters and high penetrance in sons. The high-risk families come from (mostly female) children who carry a new causative mutation but are unaffected and transmit the dominant mutation to grandchildren.

Epigenetic

Several epigenetic models of autism have been proposed. These are suggested by the occurrence of autism in individuals with fragile X syndrome, which arises from epigenetic mutations, and with Rett syndrome, which involves epigenetic regulation factors. An epigenetic model would help explain why standard genetic screening strategies have so much difficulty with autism.

Genomic imprinting

Genomic imprinting models have been proposed; one of their strengths is explaining the high male-to-female ratio in ASD. One hypothesis is that autism is in some sense diametrically opposite to schizophrenia and other psychotic-spectrum conditions, that alterations of genomic imprinting help to mediate the development of these two sets of conditions, and that ASD involves increased effects of paternally expressed genes, which regulate overgrowth in the brain, whereas schizophrenia involves maternally expressed genes and undergrowth.

Environmental interactions

Though autism's genetic factors explain most of autism risk, they do not explain all of it. A common hypothesis is that autism is caused by the interaction of a genetic predisposition and an early environmental insult. Several theories based on environmental factors have been proposed to address the remaining risk. Some of these theories focus on prenatal environmental factors, such as agents that cause birth defects; others focus on the environment after birth, such as children's diets. All known teratogens (agents that cause birth defects) related to the risk of autism appear to act during the first eight weeks from conception, strong evidence that autism arises very early in development. Although evidence for other environmental causes is anecdotal and has not been confirmed by reliable studies, extensive searches are underway.

Sex bias

Autism spectrum disorder effects all races, ethnicity, and socioeconomic groups. Still, more males than females are affected across all cultures, the ratios of males- to - females is appropriately 3 to 1. A study analyzed the Autism Genetics Resource Exchange (AGRE database), which holds resources, research, and records of autism spectrum disorder diagnosis From this study, it was concluded, that when spontaneous mutation cause autism spectrum disorder (ASD), there is high penetrance in males and low penetrance in females. A study in published 2020 explored the reason behind this idea further. It is known that the main difference between males and females is males have one X and one Y sex chromosome whereas female have two X chromosomes. This leads to the idea that there is a gene on the X chromosome that is not on the Y that is involved with the sex bias of ASD.

In another study, it has been found that the gene called NLGN4, when mutated, can cause ASD. This gene and other NLGNs gene are important for neuron communications. This NLGN4 gene is found on both the X (NLGN4X) and the Y (NLGN4Y) chromosome. The sex chromosomes are 97% identical. When this gene has been studied, most of the mutation that occur are on NLGN4X. Research into the difference between NLGN4X and NLGN4Y found that the NLGN4Y protein has poor surface expectations and poor synapses regulations, leading to poor neuron communication. Researchers concluded that males have a higher- incidences of autism when the mechanism is NLGN4X-associated. This association was concluded since females have two X chromosomes, if there is a mutation in a gene on a X chromosomes the other X chromosome can be used to compensate for mutation. Whereas males only have one X chromosome, meaning that if there is a mutation in a gene on a X chromosome, that that is the only copy of the gene had and it will be used. The genomic difference between males and females is one mechanism that leads to the higher incidence of ASD in males.

Candidate gene loci

Known genetic syndromes, mutations, and metabolic diseases account for up to 20% of autism cases. A number of alleles have been shown to have strong linkage to the autism phenotype. In many cases the findings are inconclusive, with some studies showing no linkage. Alleles linked so far strongly support the assertion that there is a large number of genotypes that are manifested as the autism phenotype. At least some of the alleles associated with autism are fairly prevalent in the general population, which indicates they are not rare pathogenic mutations. This also presents some challenges in identifying all the rare allele combinations involved in the etiology of autism.

A 2008 study compared genes linked with autism to those of other neurological diseases, and found that more than half of known autism genes are implicated in other disorders, suggesting that the other disorders may share molecular mechanisms with autism.

Primary

Gene OMIM/# Locus Description
CDH9, CDH10
5p14.1 A 2009 pair of genome-wide association studies found an association between autism and six single-nucleotide polymorphisms in an intergenic region between CDH10 (cadherin 10) and CDH9 (cadherin 9). These genes encode neuronal cell-adhesion molecules, implicating these molecules in the mechanism of autism.
CDH8
16q21 A family based study identified a deletion of CDH8 that was transmitted to three out of three affected children and zero out of four unaffected siblings. Further evidence for the role of CDH8 comes from a spontaneous 1.52 megabase inversion that disrupts the gene in an affected child.
MAPK3
16p11.2 A 2008 study observed a de novo deletion of 593 kb on this chromosome in about 1% of persons with autism, and similarly for the reciprocal duplication of the region. Another 2008 study also found duplications and deletions associated with ASD at this locus. This gene encodes ERK1, one of the extracellular signal regulated kinase subfamily of mitogen-activated protein kinases which are central elements of an intracellular signaling pathways that transmits signals from cell surfaces to interiors. 1% of autistic children have been found to have either a loss or duplication in a region of chromosome 16 that encompasses the gene for ERK1. A similar disturbance in this pathway is also found in neuro-cardio-facial-cutaneous syndromes (NCFC), which are characterized by cranio-facial development disturbances that also can be found in some cases of autism.
SERT (SLC6A4)
17q11.2 This gene locus has been associated with rigid-compulsive behaviors. Notably, it has also been associated with depression but only as a result of social adversity, although other studies have found no link. Significant linkage in families with only affected males has been shown. Researchers have also suggested that the gene contributes to hyperserotonemia. However, a 2008 meta-analysis of family- and population-based studies found no significant overall association between autism and either the promoter insertion/deletion (5-HTTLPR) or the intron 2 VNTR (STin2 VNTR) polymorphisms.
CACNA1G
17q21.33 Markers within an interval containing this gene are associated with ASD at a locally significant level. The region likely harbors a combination of multiple rare and common alleles that contribute to genetic risk for ASD.
GABRB3, GABRA4
multiple GABA is the primary inhibitory neurotransmitter of the human brain. Ma et al. (2005) concluded that GABRA4 is involved in the etiology of autism, and that it potentially increases autism risk through interaction with GABRB1. The GABRB3 gene has been associated with savant skills. The GABRB3 gene deficient mouse has been proposed as a model of ASD.
EN2
7q36.2 Engrailed 2 is believed to be associated with cerebellar development. Benayed et al.. (2005) estimate that this gene contributes to as many as 40% of ASD cases, about twice the prevalence of the general population. But at least one study has found no association.
?
3q25-27 A number of studies have shown a significant linkage of autism and Asperger syndrome with this locus. The most prominent markers are in the vicinity of D3S3715 and D3S3037.
RELN
7q21-q36 In adults, Reelin glycoprotein is believed to be involved in memory formation, neurotransmission, and synaptic plasticity. A number of studies have shown an association between the REELIN gene and autism, but a couple of studies were unable to duplicate linkage findings.
SLC25A12
2q31 This gene encodes the mitochondrial aspartate/glutamate carrier (AGC1). It has been found to have a significant linkage to autism in some studies, but linkage was not replicated in others, and a 2007 study found no compelling evidence of an association of any mitochondrial haplogroup in autism.
HOXA1 and HOXB1
multiple A link has been found between HOX genes and the development of the embryonic brain stem. In particular, two genes, HOXA1 and HOXB1, in transgenic 'knockout' mice, engineered so that these genes were absent from the genomes of the mice in question, exhibited very specific brain stem developmental differences from the norm, which were directly comparable to the brain stem differences discovered in a human brain stem originating from a diagnosed autistic patient.

Conciatori et al.. (2004) found an association of HOXA1 with increased head circumference. A number of studies have found no association with autism. The possibility remains that single allelic variants of the HOXA1 gene are insufficient alone to trigger the developmental events in the embryo now associated with autistic spectrum conditions. Tischfield et al.. published a paper which suggests that because HOXA1 is implicated in a wide range of developmental mechanisms, a model involving multiple allelic variants of HOXA1 in particular may provide useful insights into the heritability mechanisms involved. Additionally, Ingram et al.. alighted upon additional possibilities in this arena. Transgenic mouse studies indicate that there is redundancy spread across HOX genes that complicate the issue, and that complex interactions between these genes could play a role in determining whether or not a person inheriting the requisite combinations manifests an autistic spectrum condition—transgenic mice with mutations in both HOXA1 and HOXB1 exhibit far more profound developmental anomalies than those in which only one of the genes differs from the conserved 'norm'.

In Rodier's original work, teratogens are considered to play a part in addition, and that the possibility remains open for a range of teratogens to interact with the mechanisms controlled by these genes unfavourably (this has already been demonstrated using valproic acid, a known teratogen, in the mouse model).

PRKCB1
16p11.2 Philippi et al. (2005) found a strong association between this gene and autism. This is a recent finding that needs to be replicated.
TAOK2
16p11.2 Richter et al. (2018) found a strong association between this gene and autism.
MECP2 300496, AUTSX3 Xq28 Mutations in this gene can give rise to autism spectrum disorders and related postnatal neurodevelopmental disorders.
UBE3A
15q11.2–q13 The maternally expressed imprinted gene UBE3A has been associated with Angelman syndrome. MeCP2 deficiency results in reduced expression of UBE3A in some studies.
SHANK3 (ProSAP2)
22q13 The gene called SHANK3 (also designated ProSAP2) regulates the structural organization of neurotransmitter receptors in post-synaptic dendritic spines making it a key element in chemical binding crucial to nerve cell communication. SHANK3 is also a binding partner of chromosome 22q13 (i.e. a specific section of Chromosome 22) and neuroligin proteins; deletions and mutations of SHANK3, 22q13 (i.e. a specific section of Chromosome 22) and genes encoding neuroligins have been found in some people with autism spectrum disorders.

Mutations in the SHANK3 gene have been strongly associated with the autism spectrum disorders. If the SHANK3 gene is not adequately passed to a child from the parent (haploinsufficiency) there will possibly be significant neurological changes that are associated with yet another gene, 22q13, which interacts with SHANK3. Alteration or deletion of either will effect changes in the other.

A deletion of a single copy of a gene on chromosome 22q13 has been correlated with global developmental delay, severely delayed speech or social communication disorders and moderate to profound delay of cognitive abilities. Behavior is described as "autistic-like" and includes high tolerance to pain and habitual chewing or mouthing (see also 22q13 deletion syndrome). This appears to be connected to the fact that signal transmission between nerve cells is altered with the absence of 22q13.

SHANK3 proteins also interact with neuroligins at the synapses of the brain further complicating the widespread effects of changes at the genetic level and beyond.

NLGN3 300425, AUTSX1 Xq13 Neuroligin is a cell surface protein (homologous to acetylcholinesterase and other esterases) that binds to synaptic membranes. Neuroligins organize postsynaptic membranes that function to transmit nerve cell messages (excitatory) and stop those transmissions (inhibitory); In this way, neuroligins help to ensure signal transitions between nerve cells. Neuroligins also regulate the maturation of synapses and ensure there are sufficient receptor proteins on the synaptic membrane.

Mice with a neuroligin-3 mutation exhibit poor social skills but increased intelligence. Though not present in all individuals with autism, these mutations hold potential to illustrate some of the genetic components of spectrum disorders. However, a 2008 study found no evidence for involvement of neuroligin-3 and neuroligin-4x with high-functioning ASD.

MET
7q31 The MET gene (MET receptor tyrosine kinase gene) linked to brain development, regulation of the immune system, and repair of the gastrointestinal system, has been linked to autism. This MET gene codes for a protein that relays signals that turn on a cell's internal machinery. Impairing the receptor's signaling interferes with neuron migration and disrupts neuronal growth in the cerebral cortex and similarly shrinks the cerebellum—abnormalities also seen in autism.

It is also known to play a key role in both normal and abnormal development, such as cancer metastases. A mutation of the gene, rendering it less active, has been found to be common amongst children with autism. Mutation in the MET gene demonstrably raises risk of autism by 2.27 times.

NRXN1
2q32 In February 2007, researchers in the Autism Genome Project (an international research team composed of 137 scientists in 50 institutions) reported possible implications in aberrations of a brain-development gene called neurexin 1 as a cause of some cases of autism. Linkage analysis was performed on DNA from 1,181 families in what was the largest-scale genome scan conducted in autism research at the time.

The objective of the study was to locate specific brain cells involved in autism to find regions in the genome linked to autism susceptibility genes. The focus of the research was copy number variations (CNVs), extra or missing parts of genes. Each person does not actually have just an exact copy of genes from each parent. Each person also has occasional multiple copies of one or more genes or some genes are missing altogether. The research team attempted to locate CNVs when they scanned the DNA.

Neurexin 1 is one of the genes that may be involved in communication between nerve cells (neurons). Neurexin 1 and other genes like it are very important in determining how the brain is connected from cell to cell, and in the chemical transmission of information between nerve cells. These genes are particularly active very early in brain development, either in utero or in the first months or couple of years of life. In some families their autistic child had only one copy of the neurexin 1 gene.

Besides locating another possible genetic influence (the findings were statistically insignificant), the research also reinforced the theory that autism involves many forms of genetic variations.

A 2008 study implicated the neurexin 1 gene in two independent subjects with ASD, and suggested that subtle changes to the gene might contribute to susceptibility to ASD.

A Neurexin 1 deletion has been observed occurring spontaneously in an unaffected mother and was passed on to an affected child, suggesting that the mutation has incomplete penetrance.

CNTNAP2
7q35-q36 Multiple 2008 studies have identified a series of functional variants in the CNTNAP2 gene, a member of the neurexin superfamily, that implicate it as contributing to autism.
FOXP2
7q31 The FOXP2 gene is of interest because it is known to be associated with developmental language and speech deficits. A 2008 study found that FOXP2 binds to and down-regulates CNTNAP2, and that the FOXP2-CNTNAP2 pathway links distinct syndromes involving disrupted language.
GSTP1
11q13 A 2007 study suggested that the GSTP1*A haplotype of the glutathione S-transferase P1 gene (GSTP1) acts in the mother during pregnancy and increases the likelihood of autism in the child.
PRL, PRLR, OXTR
multiple A 2014 meta-analysis found significant associations between autism and several single-nucleotide polymorphisms in the OXTR gene.

Others

There is a large number of other candidate loci which either should be looked at or have been shown to be promising. Several genome-wide scans have been performed identifying markers across many chromosomes.

A few examples of loci that have been studied are the 17q21 region, the 3p24-26 locus, PTEN, 15q11.2–q13 and deletion in the 22q11.2 area.

Homozygosity mapping in pedigrees with shared ancestry and autism incidence has recently implicated the following candidate genes: PCDH10, DIA1 (formerly known as C3ORF58), NHE9, CNTN3, SCN7A, and RNF8. Several of these genes appeared to be targets of MEF2, one of the transcription factors known to be regulated by neuronal activity and that itself has also recently been implicated as an autism-related disorder candidate gene.

Butane

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