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To: Arleigh
Twin studies show that genetics accounts for... 50% of sexual behavior

If you're referring to a twin study that claims that 50% of the identical twins who are themselves homosexual, have a homosexual twin, there are some serious problems with that study. The first is that the sample population was self-selected by responding to adds in the back of homosexual publications.

Other less-skewed twin studies have given numbers between 10% and 20%.

But there's a problem even calling those 10% to 20% evidence of a genetic link to homosexuality... because the nature vs. nurture debate is a false dilemma. There is a third possibility...


Numerous factors can affect pre-natal development. One particulary vulnerable phase occurs when that XY chromosome kicks in the hormones and turns an externally female fetus into the male it was genetically destined to be.

What if pre-natal conditions are somehow less than optimal during that hormone surge? What is the impact on the later sexual preference of that fetus?

We don't really know, but we know that identical twins share an identical pre-natal environment.

Basically, what the twin studies of homosexuals indicates is that the cause is most likely not genetic. Here's why...

Eye color is genetic. 100% of the identical twins with blue eyes have a blue eyed twin. But when twin studies of homosexuality give an identical correlation of 10% or 20% (heck, even 50%), then we know for a fact that homosexuality isn't genetic in 50% to 90% of the cases. The bottom line is that nurture and pre-natal probably account for the bulk of the rest.

After all, wouldn't a "gay gene" have a hard time perpetuating itself?

Hard to escape the fact that homosexuals are absolutely always procreated heterosexually.

221 posted on 06/05/2002 12:08:04 AM PDT by Sabertooth
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To: Sabertooth

A combination of one or two "gay genes" could very easily define a predisposition towards homosexuality. It would then be possible to define a person not as gay or straight but as relatively gayer or straighter than the population. People on either extreme would hard-pressed to choose the opposite of their natural inclination. People closer towards the middle would be more fluid in their attractions and choice of partners.

There are straights with one or two past homosexual experiences who go on to marry and raise a family. These might be people who are mostly straight, but near enough to the boundry that a cross-over isn't unthinkable.

Conversly there are individuals gay of center who try to follow conventional norms, marry, and have a family only to later realize that they are morbidly unhappy in a hetero lifestyle.

Not really; it's basic genetics. Remember high school biology class? There are two allels for every gene. If there is a gay gene, and if it is recessive (a reasonable assumption), you will never be able to "breed it out of existence" because a person with the Gay/Straight combination will be indistinguishable from a Straight/Straight individual, but will be a "carrier" for homosexual tendencies.

Disclaimer: All of the above is conjecture and hypothesis on my part, but it does seem to fit the annecdotal facts and observations.

250 posted on 06/05/2002 11:20:58 AM PDT by Condorman
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