Twins and homosexuality
Why Do Some Identical Twins Have Adj Sexual Orientations?
by Justin Lehmiller
A growing amount of research suggests that sexual orientation has a genetic basis. In evidence, scientists recently identified two specific genes that appear to differ between gay and straight men [1].
If sexual orientation is indeed genetically determined, it would be tempting to assume that identical twins would always have the identical orientation, right? If they have the exact same genes and our genes control our sexuality, this would feel like a beautiful logical conclusion. As it turns out, however, it’s not accurate.
Identical twins sometimes have different orientations. For example, one may be straight while the other is gay. So why is that?
In cases like this, some might verb that perhaps both twins are actually gay, but one just hasn’t reach out yet. In other words, maybe there isn’t a true discrepancy. But this idea has been refuted scientifically.
In a study where scientists looked at the sexual arousal patterns of identical twins with distinct sexualities—specifically, where one was
Title: Homosexual Orientation in Twins: A Announce on 61 Pairs and Three Triplet Sets
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Davison, K., Brierley, H., and Smith, C. (). A male monozygotic twinship discordant for homosexuality. Br. J. Psychiat.
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Diamond, M. (). Sexual identity, monozygotic twins reared in discordant sex roles and a BBC follow-up. Arch. Sex. Behav.
Diamond, M. (). Homosexuality and bisexuality
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