http://www.cwfa.org/images/content/bornorbred.pdf
One of the most influential studies on the genetics of homosexuality was done by Dean Hamer and his co-workers at the National Cancer Institute in Washington DC (1993). Hamer's research involved studying thirty-two pairs of brothers who were either "exclusively or mostly" homosexual. None of the sets of brothers were related. Of the thirty-two pairs, Hamer and his colleagues found that two-thirds of them (twenty-two of the sets of brothers) shared the same type of genetic material. This strongly supports the hypothesis that there is an existing gene that influences homosexuality (4).
Hamer then looked closely at the DNA of these gay brothers to try and find the region of the X chromosome (since the earlier research suggested that the gene was passed down maternally) that most of the homosexual brothers shared. He discovered that homosexual brothers have a much higher likelihood of inheriting the same genetic sequence on the region of the X chromosome identified by Xq28, than heterosexual brothers of the same gay men. Keep in mind though, that this is just a region of the X chromosome, not a specific gene. Although researchers are hopeful, a single gene has not yet been identified (7). Hamer's study also acknowledges the fact that while it does suggest that there is a gene that influences homosexuality, it has not yet been determined how greatly the gene influences whether or not a person will be homosexual (4). In addition, Hamer attempted to locate a similar gene in female homosexuals, but was unsuccessful (7). The results that Hamer's study did find though, cannot yet be accepted as absolute truth. Another study took place in 1993 by Macke et al. This study examined the same gene locus as the Hamer study, but found that it had no influence on homosexuality (8). As you can see, the results on this topic are still extremely varied and reasonably new, so it is difficult to come to any lasting conclusion.
Other studies have been conducted that look at twin brothers rather than brothers of different ages. Bailey and Pillard (1991) did a study of twins that determined a Ò52% concordance of homosexuality in monozygotic twins, 22% for dizygotic twins, and 11% for adoptive brothers of homosexual men (8). These results, like Hamer's, provide further support for the claim that homosexuality is genetically linked. Studies very similar to the Bailey and Pillard study have been done both with female homosexual siblings and siblings of both sexes. The results for both of these studies were only off from Bailey and PillardÕs by a few percentage points. Putting all of these results together, it seems like genetics are at least 50% accountable for determining a personÕs sexual orientation (8).
Looking at the results of many of the other studies I have discussed, it seems a little strange to me that the student of homosexual siblings who were both male and female came up with similar result as the studies that looked exclusively at male homosexuality. Hamer's study, along with others, have tried to located a gene that influences female homosexuality, but they have been unsuccessful. More importantly, the region of the X chromosome that very possibly could influence male homosexuality does not influence females in the same way. Female heterosexuals merely pass the gene sequence on to their sons. Knowing this, it seems odd to me that there would be such a high percentage of male and female homosexual siblings. Perhaps this suggests that if genetics are responsible for homosexuality, we have a long way to go before we completely understand the gene loci that determine sexuality.
http://serendip.brynmawr.edu/exchange/node/1925
Hamer Hammered by New Scientific Study, FRC Says
"Science Confirms What I've Seen in My Own Life as Well as in the Lives of Thousands of Others Who Have Left the Homosexual Lifestyle," Cantu Says
WASHINGTON, April 22 /PRNewswire/ -- " Scientists are finally telling us what we've always known. There is absolutely no scientific proof of a 'gay gene,'" said Family Research Council Policy Analyst Yvette Cantu Thursday.
A study conducted in 1993 by openly "gay" activist and researcher Dr. Dean Hamer of the National Cancer Institute examined the X chromosomes of 40 pairs of homosexual brothers. The study, which appeared in the March 1993 issue of the journal Science, found that 33 of the pairs of brothers had genetic markers for male homosexuality.
A new study attempting to replicate Hamer's was released today by the same Science magazine, discrediting the 1993 study. The study conducted by scientists from the Department of Clinical Neurological Sciences at the University of Western Ontario and the Department of Genetics at Stanford Medical School concluded that "data do not support the presence of a gene of large effect influencing sexual orientation."
The Boston Globe reported in February that the media-ballyhooed "gay gene" theory was already in trouble. The Globe article featured the findings of Dr. Richard Pillard, a professor of psychiatry at Boston University's School of Medicine, whose twin studies showed "that sexuality is greatly influenced by environment, and that the role of genetics is, in the end, limited."
"These findings confirm what I've seen in my own life as well as in the lives of thousands and thousands of people who have left the lifestyle," said Cantu. "I am living proof that homosexuality is not an immutable characteristic.
Hamer himself has said that lesbianism is 'culturally transmitted, not inherited ... It's more environmental than genetic, more nurture than nature.' Will these recent studies force Hamer to concede that male homosexuality is also not a matter of genetics but of environment?
http://fathersforlife.org/gay_issues/gay_gene.htm
so do all the scientists involved have a religious agenda? looking at the sexual orientation of those who originally promoted and "researched" proving a gay gene i would say there is indeed an agenda at play and it has nothing to do with religion (well maybe roman catholocism...lol)
