You need JavaScript enabled to view it. This example of the potential power of genetics captured widespread media attention in and inspired the Minnesota Study of Twins Reared Apart.
Participants in the MTFS include families with same-sex identical or fraternal twins who were born in Minnesota. The SIBS study is comprised of adoptive and biological siblings and their parents.
You need JavaScript enabled to view it. Born Together — Reared Apart.
Why are some people gay? Most researchers who study sexual orientation think that both genetic and environmental factors play a role, but the relative contributions of each remain unclear.
For men, new research suggests that clues to sexual orientation may lie not just in the genes, but in the spaces between the DNA, where molecular marks instruct genes when to turn on and off and how strongly to express themselves. Ngun reported that in studying the genetic material of 47 pairs of identical male twins, he has identified "epigenetic marks" in nine areas of the human genome that are strongly linked to male homosexuality.
A pride march in Belgrade last month. 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.