We observed in the UK Biobank that individuals who reported same-sex sexual behavior had on average fewer offspring than those of individuals who engaged exclusively in heterosexual behavior... This reproductive deficit raises questions about the evolutionary maintenance of the trait, but we do not address these here.Yes, it certainly does raise that question. I understand that a thousand explanations have been thrown out for this, none of which has any evidence to back it, and suggest the possibility that we are working with an absurd premise.
Now let's go back to the description of "same-sex, sexual behavior." By what criteria do we group some kid who, say, had one same-sex sexual experience at summer camp with someone who identifies as homosexual. You would group such and individual as "non-heterosexual"? That seems a stretch and ignores their self-identification. Is there some causal relationship between these two things, genetic or not? I don't think anyone could realistically group these individuals together for a study of this nature. I question even doing a study of this nature, but I think that one would want to first identify individuals that are clearly homosexual rather than confound the study with what might largely be a culturally related experimentation phase.
Once again, I might add, the UK BioBank has been noted in a few recent studies to be replete with population stratification issues, notably related to age and it is noted that young people who participate have higher rates of a same-sex experience. I won't get into too much detail along these lines other than to suggest that such population stratification could easily account for the few significant loci that were found. Now, let's look at some of the numbers and the dubious claims of replication behind the fold:
