Always single genes?
On a thread from a Counter-Currents post about homosexuality, a commentator writes:
If “gayness” (i.e. total unambiguous homosexuality) is genetic, then how is it passed from generation to generation? Clearly whoever was carrying this gene wasn’t too gay to be making babies. Either that or society up until now has forced them to, thus inadvertently ensuring their survival.
I'm not sure why people always assume that complex human behaviors are always the result of a single gene, or a small number of genes - just like the HBDers and their postulated "gene(s) for altruism." The above comment is a case in point. Now, it is possible that homosexuality is due to a single gene or a small number of genes that is/are under direct selection.
However, it is equally possible - and probably more likely - that homosexual behaviors, to the extent that they are genetic, are due to the coinheritance of a number (likely more than a few) gene alleles, AND that these alleles may be maintained in the population for reasons other than homosexuality.
As theoretical examples: alleles coding for femininity in women which when inherited by sons increases chances for being gay, or genes for masculinity in men when inherited by daughters increases the probability of being a butch lesbian, or genes for creativity/aesthetic sense, which could be favorably selected for in some modern societies but which may also incline toward gayness.
So, a man inheriting, say, a mix of femininity genes and artistic genes and some other genes - all of which are adaptive on their own in specific environments - may have a greater chance of being homosexual.
In this way,a tendency toward homosexuality is an unavoidable emergent property - a side effect if you will - of happening to inherit a constellation of gene alleles that are present in populations because they are adaptive for other reasons not having anything directly to do with homosexuality.
This is a hypothesis that may be right or wrong, but is just as likely as "gay genes" or "gay uncle fitness" or "gayness as a result of viral infections."