"Older Brother Effects" and Antibodies?

Question

I learned from some tv shows and articles that the "older brother effect" (the one where a guy who has more older brothers is more likely to be gay) is associated with the antibodies against the y chromosomes produced by the mother. Is this mechanism similar to Type II hypersensitivity? So, in theory, does it mean that we can somehow "reduce" homosexuality of a younger brother by treating the mother with some antibodies (against the y chromosome) right after the birth of the 1st baby boy so that the mother will not produce her own antibodies? Don't get offensive because I am gay myself, and I am just curious about it.

Maybe it is male specific protein, I don't quite remember whether it is the chromosome or the protein.. But can we reduce the chance of the second baby boy being gay by putting some antibodies to the mom after the first baby boy is born?

Answer 1

I think that this is nonsense. In the first place there is no mechanism that I have ever heard of for antibodies to a specific chromosome, or to a chromosome at all; after that, there is no mechanism whereby an antibody made and secreted in the bloodstream could get into the nucleus.

Oh, I should add that I *do* believe that there is a genetic component to homosexuality--frankly, anybody who doubts that just doesn't want to listen to the data.

I glanced briefly at some of the background, athough I don't have my copy of PNAS at hand to read the original journal article. I believe the data, but suggestions that it could be some sort of maternal response to male-specific proteins is a bit premature. It also doesn't make a ton of sense from an evolutionary standpoint.

Answer 2

since homosexuality is NOT a disease, no "treatment" of this type would be ethical, even if it were medically feasible.