Homosexuality and Genetics

Hello Again Mammuthus:I hope the new data pans out and we all get to see you collecting your Nobel Prize. See, this is where I have my biggest problem. I do not discount the internal environmentpink sasquatch as done a wonderful job of convincing me of thatbut cultural practices? While I’d agree that these may influence whether or not somebody comes out of the closest, or acts upon their homosexual desires I’d have a hard time accepting that these influence whether or not one is gay. ManI need to go back to school and take another genetics course. How does culture affect height? Or are you referring to the internal (biological) environment? I guess I define it that way.

I have a friend who had 3 children by her first husband before he came out of the closet.Culture can have a lot to do with behavior.

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

I believe there are some phenotypes that are solely determined by maternal genotype; however, I seriously doubt that human homosexuality is one of those. There is also considerable "interaction" between the maternal and embryonic genomes - in other words, the genotypes of both mother and embryo effect both the uterine environment and development. It may be the result of this interaction that leads to development of sexual preference.A maternal genotype effect may make sense in an evolutionary model similar to what Crash suggested - a genotype associated with high fertility in the mother may produce homosexuality in a subset of her offspring or male siblings, ensuring extra caregivers and overall increased survival of "fertile" offspring. I'd agree more or less (there may be a "gay genotype" that guarantees homosexuality, rather than predisposes it - a nit). Hopefully helpful: Rather than referring to a "gay gene", use of the term "complex trait" or "polygenic trait" might clear up your position, which is that there is not a single gene.I also agree with you that biological homosexuality is separate of behavioral homosexuality. If a homosexual man chooses a female partner for cultural reasons, that man is still a homosexual.However, the disconnect between homosexuality at the biological and behavioral levels surely confounds genetic analysis...

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I hope the new data pans out and we all get to see you collecting your Nobel Prize.

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I would settle for it getting me a better job

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ManI need to go back to school and take another genetics course. How does culture affect height? Or are you referring to the internal (biological) environment?

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My mistake. In re-reading what I posted, it was almost John Davison-esque in poor writing. Most traits if you measure them in a population, show a bell curve distribution or normal distribution. So there are a lot of people around some mean (say height) and then smaller numbers of people as you head to the extremes. Genetic diversity looks like this to if you take the pairwise sequence diversity for a given gene (often the mitochondrial hypervariable region). Homosexuality as a trait most likely is normally distributed with the extremes being exclusive attraction to the same sex to extreme hostility to the same sex. Genes and environment play a role in shaping the distribution and in determining the mean.Yes, culture can affect height (at least potentially). If you were in a culture that abstains from eating certain types of food (partiuclarly at an early age) it could either stunt or maximize growth regardless of the underlying genetics. Though not a part of their culture, people in the devloping world who go through periods of starvation tend to be stunted in many developmental aspects including height though their genetic potential may be for greater height with appropriate diet.

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I guess I define it that way.

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but why? You would not define height by people who are 6.5 feet tall or 4 feet tall? I have a friend who was attracted to both men and women. For a while, he only slept with men...now he is married to a woman. Is he homosexual? We are talking about a behavior and though the extremes may be more obvious, the distribution is actually more relevant biologically.

RAZD: But this does not mean that the individual was not gay prior to coming out of the closest. As a matter of fact, I would take a guess that he has been gay his whole life. Whether or not (or when) he acts upon his homosexual desires is a completely different question.

I have talked to him, he was gay his whole life but felt that he had to pretend to be straight. He is much happier now that he has come out.What I am pointing out is that cultural influence is what made him try to behave straight even though he was gay.

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

Pink Sasquatch:I'm not sure I have anything more to discuss on this one. You seem to have much more eloquently expressed my opinion than I did myself...thanks. Using either the term complex trait or polygenic trait may indeed help clear up my position. Simply calling it a gay gene does imply a single loci, which was never my intent, so I hope now you have a better understanding of my position. Again, thanks for the help and info.FliesOnly

Mammuthus:Would a better job entail coming back to the States? Or is the beer over there just too good to give up? WaitI think I may be a bit confused here. You say homosexuality as a trait is normally distributed with two extremes, one being attraction to the same sex and the other being hostility (repulsion?) to the same sex. Do you really mean sexuality as a trait? Cuz if I’m repulsed by the same sex, then I certainly am not a homosexual. Anyway, I think what you’re trying to tell me (at least this is how I took it) is that if we look at any given population (say the city of Detroit) then we would find a bell shaped curve of sexual behaviorswith one tail being complete attraction to members of the same sex and the other tail being complete attraction to the opposite sex. However, wouldn’t this mean that the Bell Shaped portion of the curve covers the largest chunk of the population, and that they would show an equal attraction to both sexesthat the majority of the population would be bisexual? I’m sure that this is NOT what you mean, so I must be missing something here. While this is true, I will remain stubborn here and state that I have serious doubts that anything like this plays a role in homosexuality. I say this because we see homosexuality in all cultures, so there would have to be some common cross cultural aspect that could potentially have an effect on sexual preferenceI just don’t see that being the case. As I have said, I do not doubt that many biological environmental factors probably do play a role during development, I just can’t see post-birth culture playing any role what-so-ever (perhaps in the coming out of the closet idea (see posts 32 and 35), but not in determining sexual preferences). This is a tough one for me. I’m not gay, so I have absolutely no point of reference from which to form an opinion. For example, I have no desire what-so-ever to engage in any form of sexual activity with members of the same sex (but at the same timemetwo womenyikes!...), so I have a hard time understanding how someone can be bisexual. To me, they’re probably gay but society has forced them to be attracted to members of the opposite sex. But they’re still gay, despite their cultural behavior. I’m not passing judgment on them, so please don’t think thatI just see it as more of a case of black and white I guess.

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Would a better job entail coming back to the States? Or is the beer over there just too good to give up?

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I'll probably be sticking with the beer...but it may not be German for long if the economy does not pick up...or a government run by people with functional brains does not get elected soon.

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that the majority of the population would be bisexual? I’m sure that this is NOT what you mean, so I must be missing something here.

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Not bisexual per se. But men and women may find people of the same sex attractive even if they do not act on the impulse and are exclusively heterosexual. And I think culture plays a strong role in how far people might act on their attractions. If one is bi or finds members of both sex at least attractive but lives in a place where such attraction is penalized, then I think most people would eventually end up heterosexual and never explore a same sex relationship. In a permissive society, it might play out differently. Think about how US culture demonizes sex of any kind with such stupid myths as the simple act of masturbation leading to going blind or getting hairy palms...it is amazing anyone grows up and has sex at all.

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I say this because we see homosexuality in all cultures, so there would have to be some common cross cultural aspect that could potentially have an effect on sexual preference

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There are many common cross cultural phenomena. I don't see why this would be prohibitive. I don't even see why the kinds of variations in androgen exposure etc. would also not be common among different human populations. Couple that with a probable similar genetic component underlying the behavior (and possible positive selection) and it becomes less surprising to see the behavior show up repeatedly in different groups.

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This is a tough one for me. I’m not gay, so I have absolutely no point of reference from which to form an opinion. For example, I have no desire what-so-ever to engage in any form of sexual activity with members of the same sex (but at the same timemetwo womenyikes!...), so I have a hard time understanding how someone can be bisexual. To me, they’re probably gay but society has forced them to be attracted to members of the opposite sex. But they’re still gay, despite their cultural behavior. I’m not passing judgment on them, so please don’t think thatI just see it as more of a case of black and white I guess.

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I can appreciate that you don't understand the feeling. I am not gay either and am not attracted to men so is not that I can imagine the desire either.I am also not 6 feet tall but I recognize that it is a trait that is variable and that other people can be taller or shorter than me even though I will never experience it. Predisposition to depression, height, risk behavior, or just about anything else varies to. I don't know what it is like to be Chinese, or Mexican. There is no black and white in biology and certainly not behavior. Particularly behavior because in addition to genetics and environment, you have variation in cultural environment all of which can influence the trait in question.

To me this is the nail in the coffin on the concept of there being a choice: When you get right down to it (), there is absolutely no difference in the actions of oral or manual sex -- the sex of the mouth or hand does not affect the action -- and thus should be equally accepted by all from anyone ... and yet the fact is that this is NOT the case.

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

Isn't it about time you guys stop guessing and start asking the real expert (moi) here?

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He's not dead. He's electroencephalographically challenged.The longest word in the English language is pneumonoultramicroscopicsilicovolcanoconiosis.

Lam:Bout time! I've been floundering basically by myself, hoping you would jump in, but alas...I was left to answer questions all by myself...