|Two women kissing illustration|
Scientists have claimed they have pinpointed the reason behind homosexuality, according to press reports.
The answer may lie in epigenetics, or how gene expression is controlled by "temporary switches," known as epi-marks, researchers from the National Institute for Mathematical and Biological Synthesis explained in a study released this week.
Sex-specific epi-brands are often "deleted" from generation to generation. However, when they do not disappear, they can be transmitted from father to daughter or mother to son, leading to homosexuality in children, scientists suspect.
"The transmission of antagonistic epi-marks between generations is the most plausible evolutionary mechanism of the phenomenon of human homosexuality," Sergey Gavrilets, the study co-author, said in a statement.
Researchers have long believed that sexual orientation has a heritable component. However, scientists say that homosexuality, in terms of evolution, cannot be the only genetic reason because they eventually disappear because homosexuals are not expected to reproduce.