Stanton L. Jones writes about what the research shows in First Things.

Excerpt:

Frank Bruni, in his essay “Genetic or Not, Gay Will Not Go Away“(New York Times, January 28, 2012), makes a broad point regarding which I am in complete agreement: Our societal, legal, and cultural debates will not be solved by science. But when you do cite the science, you ought to get it right.

[…]In support of the argument that at least sometimes sexual orientation is a condition of birth, Bruni describes how “One landmark study looked at gay men’s brothers and found that 52% of identical twin brothers were also gay.” This brief explanation both fails as a description of that 20+ year old study and fails to reflect the better research published since.

Bruni gets the number right; the 1990 landmark study by Bailey and Pillard reported a 52% “probandwise concordance” for homosexual orientation among genetically identical sibling groups, but this does not mean what Bruni says it means. A proband wise concordance is a technical calculation, one that in this case results from the following actual results: There were 41 genetically identical sibling groups (40 identical twin pairs and one triplet trio) and of these 41 groups, only in 14 of the groups did the genetically identical brothers match for sexual orientation; in the remaining 27 sets the identical twin brothers did not match.

But this 1990 study was actually based on a sample that was apparently distorted by volunteer bias and hence not representative of homosexual persons in general. Bailey’s own study of a decade later, and the recently published “gold standard” study by Långström et. al. of the Swedish Twin Registry, both found even lower matching among identical twins with much larger and more representative samples. Both studies reported about 10% matching (for Långström, 7 identical twin pairs matched with both identical brothers gay out of 71 total pairs of male identical twin pairs).

So in plain English, the best contemporary scientific findings are that when one identical twin brother is gay, the probabilities of the second twin being gay are approximately 10%. This suggests that the contribution of genetics to the determination of homosexual orientation is modest at best.

When forming your views on any controversial issue, it’s important to get your facts straight.

My previous post discusses what the peer-reviewed research shows about homosexuality.

Muddling Towards Maturity writes about a new paper about homosexuality.

Excerpt:

Stanton L. Jones, provost and professor of psychology at Wheaton College, has for years been a student of the latest research on homosexuality.  His most recent article, “Same-Sex Science: The social sciences cannot settle the moral status of homosexuality,” was published in the February 2012 issue of First Things magazine (http://www.firstthings.com/article/2012/01/same-sex-science) and is a condensed version of his longer paper with citations,“Sexual Orientation and Reason: On the implications of False Beliefs about Homosexuality” (http://www.wheaton.edu/CACE/Hot-Topic)

Stanton offers authoritative analysis of current research.  He sets the record straight and corrects popular misimpressions.  I am posting the links in anticipation of giving these two articles a careful reading at my earliest opportunity.  Stanton previously published (with Mark A. Yarhouse) in 2000, “Homosexuality: the Use of Scientific Research in the Church’s Moral Debate.”

I read over the condensed version of the paper, and found some interesting things.

Regarding the healthiness of homosexuality:

Evelyn Hooker, in her 1957 study, was careful to reject only the claim that homosexuality is always pathological. She never made the logically distinct assertion that homosexual persons on average are just as psychologically healthy as heterosexuals. It is well that she did not, because the consistent findings of the best, most representative research suggest the contrary, despite a few scattered compatible findings from smaller studies of less representative samples. One of the most exhaustive studies ever conducted, published in 2001 in the American Journal of Public Health and directed by researchers from Harvard Medical School, concludes that “homosexual orientation . . . is associated with a general elevation of risk for anxiety, mood, and substance-use disorders and for suicidal thoughts and plans.” Other and more recent studies have found similar correlations, including studies from the Netherlands, one of the most gay-affirming social contexts in the world. Depression and substance abuse are found to be on average 20 to 30 percent more prevalent among homosexual persons. Teens manifesting same-sex attraction report suicidal thoughts and attempts at double to triple the rate of other teens. Similar indicators of diminished physical health emerge in this literature.

And regarding the notion of being born gay:

Recent studies show that familial, cultural, and other environmental factors contribute to same-sex attraction. Broken families, absent fathers, older mothers, and being born and living in urban settings all are associated with homosexual experience or attraction. Even that most despised of hypothesized causal contributors, childhood sexual abuse, has recently received significant empirical validation as a partial contributor from a sophisticated thirty-year longitudinal study published in the Archives of Sexual Behavior. Of course, these variables at most partially determine later homosexual experience, and most children who experienced any or all of these still grow up heterosexual, but the effects are nonetheless real.

To say that psychological and environmental variables play a part in causation does not mean that biology does not, rather just not to the extent that many gay-affirming scholars claim. The two most influential contemporary theories of biological causation focus respectively on fraternal birth order and genetics; each has some level of support, but for modest-sized causal effects at best.

[…]Contrary to the assumptions of many social conservatives, biology does appear to play a modest part in determining sexual orientation. Contrary to the assumptions of many social progressives, psychological and environmental variables also appear to play at least a modest part in determining sexual orientation.

And what about reparative therapy?

Is sexual orientation immutable? With Mark Yarhouse of Regent University, I recently studied people seeking to change their sexual orientation. We assessed the sexual orientations and psychological distress levels of 98 individuals (72 men, 26 women) trying to change their sexual orientation through ministries organized under Exodus International, beginning early in the process and following them over six to seven years with five additional, independent assessments. Our original round of findings was published in a book titled Ex-Gays?; the latest round, in theJournal of Sex and Marital Therapy.

Of the 61 subjects who completed the study, 23 percent reported success in the form of “conversion” to heterosexual orientation and functioning, while 30 percent reported they were able to live chastely and had disidentified themselves from homosexual orientation. On the other hand, 20 percent reported giving up and fully embracing homosexual identity, and the remaining 27 percent continued the process of attempted change with limited and unsatisfactory success.

Are heterosexual and homosexual relationships the same?

Even so, intriguing hints of differences, of “nonequivalency,” between heterosexual and homosexual couples emerge from Peplau and Fingerhut’s survey. They mention one large study that found that 28 percent of lesbians had had sex outside their primary relationship—comparable to the 21 percent of women in relationships with men and 26 percent of men in relationships with women. By contrast, 82 percent of gay men had had sex with someone other than their main partner. However one construes such a striking difference in sexual monogamy, whether as a trivial stylistic difference or as indicative of something fundamental and pervasive, such a finding seriously challenges the equivalency hypothesis.

Stability is a relational characteristic of direct relevance to the types of functional concerns intrinsic, for instance, to evaluation for adoption fitness. How does equivalence look in this area? Peplau and Fingerhut cite one study that found that over a five-year period, 7 percent of married heterosexual couples broke up, compared with 14 percent of cohabiting male couples and 16 percent of cohabiting lesbian couples. They also summarize, without mentioning specific numbers, a more representative study from Norway and Sweden, which have sanctioned same-sex partnerships since the 1990s, reporting “that the rate of dissolution within five years of entering a legal union is higher among same-sex partnerships than among heterosexual marriages, with lesbian couples having the highest rates of dissolution.” Their rendering underplays the magnitude of the actual findings, which was that gay male relationships are 50 percent more likely to break up than heterosexual marriages, while lesbian relationships are 167 percent more likely to break up than heterosexual marriages. Odd that they would not mention these actual numbers.

There’s more – I just cited a few bits that jumped out at me.

I recommend reading the condensed paper just to get an idea of what the issues are and what the research says.