Study Finds Epigenetics, Not Genetics, Underlies Homosexuality
Epigenetics – how gene expression is regulated by temporary switches, called epi-marks - appears to be a critical and overlooked factor contributing to the long-standing puzzle of why homosexuality occurs.
By NIMBioS | webmaster

@matt-ruins-feminisms-shit Tagging you because you were the one who introduced me to the idea that maybe homosexuality wasn’t a ‘from birth’ thing.

Because I witnessed a fight on facebook, I would like to point out that there is no ‘victory’ or ‘homophobia’ or whatever here. This is seeking the truth. Whatever the truth is, we treat each other like human motherfucking beings. One thing I’m sure of is that homosexuality is not a conscious choice (save for Tumblr who thinks having BPD is a wonderful thing…). There is also no moral wrongdoing concerning homosexuality as well as a “no immediate harm” standard for moral judgment.

Epigenetics, in short, is the study of how the environment can change your gene expression. In the nurture vs nature debate - aka environment vs genetics debate, it can be thought of how the nurture shapes nature.

In short, this study has found that homosexuality may be due to environmental factors and their effects on genetics.

Sex-specific epi-marks produced in early fetal development protect each sex from the substantial natural variation in testosterone that occurs during later fetal development. Sex-specific epi-marks stop girl fetuses from being masculinized when they experience atypically high testosterone, and vice versa for boy fetuses. Different epi-marks protect different sex-specific traits from being masculinized or feminized – some affect the genitals, others sexual identity, and yet others affect sexual partner preference. However, when these epi-marks are transmitted across generations from fathers to daughters or mothers to sons, they may cause reversed effects, such as the feminization of some traits in sons, such as sexual preference, and similarly a partial masculinization of daughters.  

The study solves the evolutionary riddle of homosexuality, finding that “sexually antagonistic” epi-marks, which normally protect parents from natural variation in sex hormone levels during fetal development, sometimes carryover across generations and cause homosexuality in opposite-sex offspring. The mathematical modeling demonstrates that genes coding for these epi-marks can easily spread in the population because they always increase the fitness of the parent but only rarely escape erasure and reduce fitness in offspring.

Considering part of statistically normative masculinization and feminization is heterosexuality towards the appropriate sex, this may point to some interesting reach in our future surrounding the LGBT.

One weakness is that, as stated in the summary, this is more about masculinization and feminization, not necessarily homosexuality/heterosexuality. However, it might give us clues as to the causes of homosexuality. What do we do with that information? Well, that’s not up to ‘we’, but up to each of us individually. Fundamentalist christians may want to avoid these behaviors while others may be all like ‘huh. that’s an interesting tidbit’.

“When we assign morality to something that’s based on genetics, we get into a lot of trouble. In the Middle Ages, people who were left-handed were thought to be evil. We know that’s not true. We don’t believe that anymore, but that was a belief.” - Will Batts, executive director of the Memphis Gay and Lesbian Community Center

- Mod Disgruntled Clown

It really makes me mad when people call people gay as an insult and it makes me even madder when people get so offensive, like that’s the worst thing they’ve been insulted with, for a word that’s not even an insult.