Focus on the Family Will Keep your Kid from Being Gay

There have been studies in humans particularly a linkage study from 1993 to Xp28 which was not reproducible (no pun intended). However, there has been a more recent study with higher density linkage maps and a larger cohort analyzed.

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Hum Genet. 2005 Mar;116(4):272-8. Epub 2005 Jan 12. Related Articles, Links

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A genomewide scan of male sexual orientation.

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Mustanski BS, Dupree MG, Nievergelt CM, Bocklandt S, Schork NJ, Hamer DH.

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Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA. bmustanski@psych.uic.edu

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This is the first report of a full genome scan of sexual orientation in men. A sample of 456 individuals from 146 families with two or more gay brothers was genotyped with 403 microsatellite markers at 10-cM intervals. Given that previously reported evidence of maternal loading of transmission of sexual orientation could indicate epigenetic factors acting on autosomal genes, maximum likelihood estimations (mlod) scores were calculated separated for maternal, paternal, and combined transmission. The highest mlod score was 3.45 at a position near D7S798 in 7q36 with approximately equivalent maternal and paternal contributions. The second highest mlod score of 1.96 was located near D8S505 in 8p12, again with equal maternal and paternal contributions. A maternal origin effect was found near marker D10S217 in 10q26, with a mlod score of 1.81 for maternal meioses and no paternal contribution. We did not find linkage to Xq28 in the full sample, but given the previously reported evidence of linkage in this region, we conducted supplemental analyses to clarify these findings. First, we re-analyzed our previously reported data and found a mlod of 6.47. We then re-analyzed our current data, after limiting the sample to those families previously reported, and found a mlod of 1.99. These Xq28 findings are discussed in detail. The results of this first genome screen for normal variation in the behavioral trait of sexual orientation in males should encourage efforts to replicate these findings in new samples with denser linkage maps in the suggested regions.

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Since my post doing so was ignored by everyone (including holmes) I will post the most recent study demonstrating four loci associated with sexual orientation in humans. I will point out that ALL behavioral traits are quantitative traits (like height) and are influenced by both genes and environment. Even phenotypes caused by a single gene (think of cystic fibrosis) are influenced by environment and by the products of other genes (which are also part of your environment). So the entire concept of a "gay gene" is inherently ridiculous. But that does not mean it is a behavior governed by a concious choice any more than being tall would be.

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There have been studies in humans particularly a linkage study from 1993 to Xp28 which was not reproducible (no pun intended). However, there has been a more recent study with higher density linkage maps and a larger cohort analyzed.

​

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Hum Genet. 2005 Mar;116(4):272-8. Epub 2005 Jan 12. Related Articles, Links
A genomewide scan of male sexual orientation.

​

Mustanski BS, Dupree MG, Nievergelt CM, Bocklandt S, Schork NJ, Hamer DH.

​

Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA. bmustanski@psych.uic.edu

​

This is the first report of a full genome scan of sexual orientation in men. A sample of 456 individuals from 146 families with two or more gay brothers was genotyped with 403 microsatellite markers at 10-cM intervals. Given that previously reported evidence of maternal loading of transmission of sexual orientation could indicate epigenetic factors acting on autosomal genes, maximum likelihood estimations (mlod) scores were calculated separated for maternal, paternal, and combined transmission. The highest mlod score was 3.45 at a position near D7S798 in 7q36 with approximately equivalent maternal and paternal contributions. The second highest mlod score of 1.96 was located near D8S505 in 8p12, again with equal maternal and paternal contributions. A maternal origin effect was found near marker D10S217 in 10q26, with a mlod score of 1.81 for maternal meioses and no paternal contribution. We did not find linkage to Xq28 in the full sample, but given the previously reported evidence of linkage in this region, we conducted supplemental analyses to clarify these findings. First, we re-analyzed our previously reported data and found a mlod of 6.47. We then re-analyzed our current data, after limiting the sample to those families previously reported, and found a mlod of 1.99. These Xq28 findings are discussed in detail. The results of this first genome screen for normal variation in the behavioral trait of sexual orientation in males should encourage efforts to replicate these findings in new samples with denser linkage maps in the suggested regions.

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I am pressed for time these days so have reduced my posting. Like you, I found Tal's assertions that there is no data in support of a genetic basis for homosexuality to be based on his abundant reserves of ignorance and unwillingness to research before posting.To elaborate a bit, my point was exactly that there is a genetic component to homosexuality just as there is to skin color, height, weight etc. (since weight was also brought up as a choice by Tal, I guess he also never bothered to look up Leptin or the Leptin receptor). Behavioral traits are particularly hard to quantify for example, the genetics underlying bisexual orientation may differ from those of "pure" homosexuality....the consequence when doing such a study is to increase the noise and lose the signal when trying to map the traits. However, environment will also have an impact on behavioral and non-behavioral traits. Just because you have the genetic background to be 2 meters tall does not mean you will achieve this height. Malnutrition, hormones, etc. could conspire to prevent you from acheiving this potential. This applies to single gene traits for example the phenomenon of penetrance. Mutations in the neurofibromatosis gene lead to the disease neurfibromatosis...but only in about 50% of the cases and thus the penetrance is 0.5. Environmental (and other genetic factors) prevent it from having a penetrance of 1.What Dean Hamer's study attempts to do is to minimize the environmental portion of sexual orientation and isolate the genetic component. As a result, they find 4 loci that link i.e. statistically correlate with the trait of male homosexuality. Note, this is how many single genes underlying disease have been mapped and how almost all genets underlying non-disease quantitative traits are found. By targetting the regions they have found with denser markers i.e. 1 CM (centimorgan) or less and testing way more individuals than they did in this study, they hope to eventually narrow down their search to the actual genes within these intervals that are involved in homosexuality. Even without having identified the genes yet, the data are compelling for a genetic component to homosexuality.The idea that people can be "turned" heterosexual or homosexual is also suspect. Under extreme social pressure or the threat of physical violence people will do many things against their own desires or better judgement. It is more akin to witholding food from children through adolescence and then claiming that they were going to be short anyway.

Though off topic, I don't know how useful it will be to this thread and it certainly won't help Tal any. He won't read the paper or do any background research. My impression from lurking, the current crop of creo's like Tal, Faith and randman studiously avoid obtaining any information that might threaten their views whether it be scientific information, political theory or history. If they can't avoid it they just dismiss it without investigation or deny its existence. I feel genuinely sorry for them as they seem to be locked in a state of fear, anger and hatred. I am actually curious as to what at all is "christian" about their worldviews. Tal in particular thinks that war is a great endeavor to be cherished as opposed to the demonstration that society has failed that all war represents. It is often said that we scientists live in an ivory tower but I am starting to think that at least in America, many people willingly live in intellectual underground bunkers and that the lack of understanding is not soley a problem of scientists failing to communicate their results to the public.Anyway, I posted the information because I saw both sides had missed the research into human sexuality. Those with an interest can dig through it (there is not all that much in terms of large scale genetic studies)...the rest can ignore it, deny it, or attribute it to the evil atheist scientist conspiracy to force conservative Americans to become gay.

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Sorry about that. Pars was slightly correct.

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I was not picking on you...I just saw the debate ping ponging between Tal and everyone else about the genetics of sexual orientation and Tal saying no work had been done on the subject. Wanted to show one of several papers that exist. I can not link to the full text here because it is a subscription based service so you will link to a request for payment.It is not conclusive in the sense that they have not isolated the genes, but is is conclusive in that they did find the associations. There are dozens of studies for cancer, Alzheimer's, etc. that provide this type of data and then go on to isolate the genes involved.

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But it may depend on what is meant by behavioral traits and influenced.

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But not all of what you listed are traits but rather behaviors as I see it. A trait would be something shared by individuals in the population that can be diseminated from generation to generation and varies...like height, weight etc. Thus, there are behavioral traits that can be mapped genetically and have a genetic basis. While some individual specific behaviors may have a genetic basis, that need not be the case. I am not trying to be ultra reductionist to say that everything we do in our life is a consequence of our genes..at least not directly. But there are behavioral traits that have a genetic component which usually is discovered when things go wrong i.e. autism, depression, predisposition to alcoholism...or even violence.

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So is the homosexuality trait more like height (the individual has no control or influence) or predisposition to alcholism/violence/obesity (the individual may be predisposed but still be able to influence)?

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More like height..though environment does influence height via nutrition and exposure to hormones etc...so one does have potentially some control. And like height it will have a range where there are people who may be predisposed genetically to homosexuality yet show no homosexual tendencies at one extreme to those who even in a social environment that puts immense pressure to be straight, will still be homosexual. Interestingly, this is also the case with many single gene diseases where the causative mutation can be present but does not lead to the mutant phenotype. About the only single gene disease that comes to mind where you basically have a 100 % chance of showing a phenotype when the genetic mutation is present is in Huntingtons syndrome.

I will have to look around a bit for a link that is open access. Stupidly, most of what I found is subscription based and copyrighted so if I link to it you will get a screen asking for a password or for you to pay. It is a pet peeve of mine since tax money supports research yet the taxpayer has to fork out money to read the results?I will see if I can find any free material.In principle you are right that you would expect a trait that does not produce progeny to die out. But since homosexuality is a spectrum, many with homosexual tendencies will continue to reproduce and thus the traits (in the form of gene combinations) will persist in the population. There may also be a selective advantage to the presence of homosexuals in the population..or like bonobos (one of the two living chimp species) use sex (even homosexual) to form social bonds and release tension. Since multiple genes and environment also play a role in determining sexuality, it is much harder for strong selection to act....the gene combinations can keep reforming as long as those carrying the individual components reproduce.

crap...this thread is going to close soon.Anyway, I found a few things that are open access that review the research on this subject (of course the genetics portion was under construction).Biology and sexual orientation - Wikipediaalso found a blog with more references to genetic studiesAttention Required! | Cloudflare