Are twins more likely to be gay

Matrilineal inheritance is also apparent in the children of same-sex couples; a male child conceived by sperm donation to one member of a lesbian partnership is more likely to be homosexual [30].

Brendan Zietsch receives funding from the Australian Research Council. He is senior author on the paper discussed. What has been elusive is knowledge of what specific gene, or genes, are involved.

An page questionnaire on the "sexuality of twins" was filled out by one or both twins. Thirty-eight pairs of monozygotic twins (34 male pairs and 4 female pairs) were found to have a concordance rate of % for homosexual orientation.

Identical twin studies point away from genetics very hard. From the link: "Research from the s2 showed that identical twins are more likely to share a sexual orientation than are fraternal twins or adopted siblings. Family, twin, and adoptee studies indicate that homosexuality and thus heterosexuality run in families.

A paradox is the occurrence of same-sex orientation in twins in that there is a higher level of concordance in monozygous twins compared to that in dizygous twins or non-twin siblings. If sexual orientation was entirely genetically determined monozygous twins would be expected to have identical sexual inclinations.

Dear Dr. Roach: I read your recent column regarding identical twins where one of the two was balding while his twin was not. Within my extended family, there are identical twin brothers, who also were almost impossible for family members to differentiate.

Twin pairs in which at least one twin is homosexual were solicited through announcements in the gay press and personal referrals from to the present. An page questionnaire on the "sexuality of twins" was filled out by one or both twins. Thirty-eight pairs of monozygotic twins (34 male pairs .