"The number of older brothers a man has may influence his sexual orientation, researchers say.
A first-born son has a 3 percent chance of being homosexual, which is standard for the population. However, the fourth son's chance of being homosexual doubles to about 6 percent. "
Interesting, it said that environment showed no effect at all so they think it's probably biological.
http://abcnews.go.com/Health/story?id=2120218&page=1
A first-born son has a 3 percent chance of being homosexual, which is standard for the population. However, the fourth son's chance of being homosexual doubles to about 6 percent. "
Interesting, it said that environment showed no effect at all so they think it's probably biological.
http://abcnews.go.com/Health/story?id=2120218&page=1