[trumandogz]

Bailey and Pillard (1991): occurrence of homosexuality among brothers

52% of identical (monozygotic) twins of homosexual men were likewise homosexual
22% of fraternal (dizygotic) twins were likewise homosexual
11% of adoptive brothers of homosexual men were likewise homosexual

Bailey and Pillard (1993): occurrence of homosexuality among sisters

48% of identical (monozygotic) twins of homosexual women were likewise homosexual (lesbian)
16% of fraternal (dizygotic) twins were likewise homosexual
6% of adoptive sisters of homosexual women were likewise homosexual

http://www.worldpolicy.org/projects/globalrights/sexorient/twins.html

[neverdem]

Thanks for the numbers & link.

[driftdiver]

Seems like all those people would have had the same environment as well as the same genes. ( aside from adoptive)

all said and done, gays make up about 2.5% of the population but are making about 90% of the noise.

[TheBattman]

And those statistics are just as easily “proven” to be environmentally based, not genetics. If a homosexual has an identical twin, is is fairly certain that that twin is raised in the same environment...