Homosexuality and sexual antagonism

More evidence to support my favorite ultimate explanation of homosexuality came out recently. Published online, Ciani's article lays out the evidence that sexually antagonistic alleles are responsible for male homosexuality. Such an allele will, when existing in a female, increase her fecundity by some mechanism, such as androphillia, an increased attraction to men. This allele, when found in men, will have the same effect. Furthermore, if this allele is found on an X chromosome, it will spend about two-thirds of its evolutionary history in women and about one third of its time in males, so even if it has a relatively weak positive effect in women it will still be selected for despite it's high cost to male reproductive success. Furthermore, since this allele is passed on through females, several key testable predictions arise. Most notably, the fitness of gay men's maternal female relatives should be higher than the fitness of straight men's maternal female relatives and the fitness of both groups' paternal female relatives should be equal. Both of these predictions were found to be true. An article in slate does a great job explaining it further.

The only bad part about the slate article were the implications at the end:
"But the word consequence suggests a sixth, less happy implication: How would gay men see themselves and be regarded in a society that understood their condition as a side effect of female evolution? Would male androphilia be treated like sickle-cell anemia—the unfortunate cost of a genetic mutation that's beneficial in other people? We medicate sickle-cell anemia. Would we medicate homosexuality?"

The answer is flatly no. We medicate sickle-cell anemia because it causes pain and discomfort to those who have it and, more importantly, we only treat it if the patient wishes it to be treated. If a treatment could be found that would reverse the effect of this allele in males it should be made available to those men who want it, but no doctor or parent would be ethically allowed to give it to a person who does not want it. Hmm, on second thought, I could see an argument for allowing parents to reverse this effect in their children, since parents are given so much leeway in the treatment of their children. Though it strikes me as terribly unethical to do so, I can't yet formulate why that treatment should not be allowed. I can understand a parent wishing to alleviate their child from a more difficult upbringing that comes with being gay in a world that treats gays unfairly, but that psychological stress comes from external sources. The teasing and discrimination should be treated, not the homosexuality.