“Baby, I was born this way,” Lady Gaga sang in a 2011 hit that quickly became a gay anthem. Indeed, over the past 2 decades, researchers have turned up considerable evidence that homosexuality isn’t a lifestyle choice, but is rooted in a person’s biology and at least in part determined by genetics. Yet actual “gay genes” have been elusive.
A new study of male twins, scheduled for presentation at the annual meeting of the American Society of Human Genetics (ASHG) in Baltimore, Maryland, today, could help explain that paradox. It finds that epigenetic effects, chemical modifications of the human genome that alter gene activity without changing the DNA sequence, may have a major influence on sexual orientation.
Related but drawing a different conclusion:
But eight major studies of identical twins in Australia, the United States and Scandinavia during the last two decades all have arrived at the same conclusion: homosexuality primarily and overwhelmingly (90%) is an acquired disposition, instead of genetic. [emphasis in original]