There is not "a" gay gene, it is much more complicated than that. But, there is a correlation to multiple genes, heredity, hormones, and biology, according to many researchers.
I think some of the very information that I found to support the genetics of sexuality, Clyde is citing to DIScredit genetic sexuality, if I understand correctly.
306995
HOMOSEXUALITY 1; HMS1
Alternative titles; symbols
SEXUAL ORIENTATION, MALE
Gene-Phenotype Relationships
1845227] [Full Text]" Bailey and Pillard (1991)
1887219] [Full Text]" LeVay (1991)
8332896] [Full Text]" Hamer et al. (1993)
Hamer (1994)
7581447] [Full Text]" Hu et al. (1995)
10213693] [Full Text]" Rice et al. (1999)
9156085] [Full Text]" Blanchard and Klassen (1997)
15645181] [Full Text]" Mustanski et al. (2005)
16369763] [Full Text]" Bocklandt et al. (2006)
http://www.omim.org/entry/306995#9
Not true, Clyde is not citing to discredit genetic sexuality, only reporting that the body of science has not reached conclusiveness on the question of whether or not folk are born gay.
For example, looking at the Abstract of the first source you shared, it remains inconclusive:
Arch Gen Psychiatry. 1991 Dec;48(12):1089-96.
A genetic study of male sexual orientation.
Bailey JM1, Pillard RC.
Author information
Abstract
Homosexual male probands with monozygotic cotwins, dizygotic cotwins, or adoptive brothers were recruited using homophile publications. Sexual orientation of relatives was assessed either by asking relatives directly, or when this was impossible, asking the probands. Of the relatives whose sexual orientation could be rated, 52% (29/56) of monozygotic cotwins, 22% (12/54) of dizygotic cotwins, and 11% (6/57) of adoptive brothers were homosexual. Heritabilities were substantial under a wide range of assumptions about the population base rate of homosexuality and ascertainment bias. However, the rate of homosexuality among nontwin biological siblings, as reported by probands, 9.2% (13/142), was significantly lower than would be predicted by a simple genetic hypothesis and other published reports. A proband's self-reported history of childhood gender non-conformity did not predict homosexuality in relatives in any of the three subsamples. Thus, childhood gender nonconformity does not appear to be an indicator of genetic loading for homosexuality. Cotwins from concordant monozygotic pairs were very similar for childhood gender nonconformity.
http://www.ncbi.nlm.nih.gov/pubmed/1845227
A genetic study of male sexual orientation.
Bailey JM1, Pillard RC.
Author information
Abstract
Homosexual male probands with monozygotic cotwins, dizygotic cotwins, or adoptive brothers were recruited using homophile publications. Sexual orientation of relatives was assessed either by asking relatives directly, or when this was impossible, asking the probands. Of the relatives whose sexual orientation could be rated, 52% (29/56) of monozygotic cotwins, 22% (12/54) of dizygotic cotwins, and 11% (6/57) of adoptive brothers were homosexual. Heritabilities were substantial under a wide range of assumptions about the population base rate of homosexuality and ascertainment bias. However, the rate of homosexuality among nontwin biological siblings, as reported by probands, 9.2% (13/142), was significantly lower than would be predicted by a simple genetic hypothesis and other published reports. A proband's self-reported history of childhood gender non-conformity did not predict homosexuality in relatives in any of the three subsamples. Thus, childhood gender nonconformity does not appear to be an indicator of genetic loading for homosexuality. Cotwins from concordant monozygotic pairs were very similar for childhood gender nonconformity.
http://www.ncbi.nlm.nih.gov/pubmed/1845227
In your research, did you find any undisputed and conclusive scientific evidence that gays are born that way?
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