(Ivanhoe Newswire) – The factors that play a role in the development of homosexuality are debated and continue to be enigmatic, but an answer could be closer than you think. According to a recent study, there may be a biological explanation for why homosexuality occurs: epigenetics.
Although not accepted by everybody, it is believed that sexual preference is linked to genetics because of past studies demonstrating that homosexuality can ‘run in the family.’
Epi-marks, the primary component of epigenetics, regulate gene expression including where and how much a gene is expressed during development. There are sex-specific epi-marks produced early on in fetal development, which affect traits such sexual identity and sexual partner preferences.
Typically each generation has newly created epi-marks, but sometimes epi-marks can be carried over from mother to son or from father to daughter. This will cause the son to have some sexual traits feminized or the daughter to be masculinized.
To further understand the relationship between these epi-marks and the occurrence of homosexuality, researchers created a biological and mathematical model using evolutionary theory, recent advances in the molecular regulation of gene expression, and androgen-dependent sexual development.
The model found that the sex-specific epi-marks could carry over from the parent to an opposite sex fetus, possibly causing homosexuality. It was also showed that homosexuality is so common amongst humans because the gene codes for these epi-marks easily spread.
“Transmission of sexually antagonistic epi-marks between generations is the most plausible evolutionary mechanism of the phenomenon of human homosexuality,” researcher Sergey Gavrilets, Associate Director for scientific activities at the National Institute for Mathematical and Biological Synthesis, was quoted as saying.
There is still more to learn on the subject of human sexuality, but now inquiring minds have a little more to think about.
Source: The Quarterly Review of Biology, December 2012