An avowed lesbian, Dr. Anne Fausto-Sterling, professor of developmental biology and gender studies at Brown University, admits "[Although the claim that homosexuality is genetic] provides a legal argument that is, at the moment, actually having some sway in court, [f]or me, it’s a very shaky place. It’s bad science and bad politics."
No genetic earmark distinguishing homosexuals from heterosexuals has ever been identified. Homosexuals and heterosexuals are genetically indistinguishable. As stated in a British medical journal, "From an evolutionary perspective, genetically determined homosexuality would have become extinct long ago because of reduced reproduction."
Indeed, taking the question further, more than 100 scientific studies indicate that change of sexual orientation is possible for many motivated individuals. The father of the Diagnostic Statistical Manual (the Bible of psychiatry), Dr. Robert Spitzer, changed his own lifetime view. He published a study in 2003 confirming that many dissatisfied homosexuals are able to make substantial long-term changes in orientation.
Another premise of the same-sex marriage debate claims homosexual coupling involves stable, long-term relationships equivalent to heterosexual marriages. Drs. David McWhirter and Andrew Mattison, both openly homosexual, studied 156 male couples who had lived together for 20 years or more. To their dismay, they found that the longest period of sexual monogamy for those couples was five years; the average was under two years.
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