A working group at the National Institute for Mathematical and Biological Synthesis (NIMBioS), based at UT, used mathematical modeling that found the transmission of sex-specific epi-marks may signal homosexuality.
According to the study, published online today in The Quarterly Review of Biology, sex-specific epi-marks, which are "erased" and thus normally do not pass between generations, can lead to homosexuality when they escape erasure and are transmitted from father to daughter or mother to son.
Epigenetics' role in homosexuality finally gets some evidentiary underpinnings--even if via mathematical modeling. The reports' language sounds too definitive though. It's early. But...I've been saying for years--with in utero endocrinological possibilities in mind--that "born this way" and "it's genetic" were potentially problematic declarations because of how people take them to mean inevitability. Genetics is complex. The possibility of homosexuality someday being made a thing of the past in developed countries through medical monitoring and intervention during pregnancy is by no means beyond the realm of possibility.
It's also further evidence that at least as far as male same-sex sexual attraction is concerned, it's maternal-line heredity that's most critical--other studies about sexually antagonistic traits have suggested this is the case.
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