Identical twins have identical genes. If homosexuality were genetically predestined (like eye color), then if one identical twin was homosexual, in 100% of the cases his brother would be too. But only about 38% of the time is the identical twin brother homosexual.
Is it possible that homosexual identical twins, raised in the same environment, have similar experiences that make them choose a homosexual identity? Or are 62% of the identical twins of homosexuals still in the closet?
http://www.narth.com/docs/whitehead2.html
2007-10-18 15:39:34 · 7 answers · asked by Bruce 7 in Society & Culture ➔ Cultures & Groups ➔ Lesbian, Gay, Bisexual, and Transgender
According to
http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=11910793&dopt=AbstractPlus
fraternal birth order accounts for only 1 in 7 cases of homosexual men, and excludes left-handed men and all women. Isn't a plausible alternative hypothesis that younger siblings of brothers are more likely to be exposed to early homosexual experiences with their brothers?
2007-10-18 16:02:31 · update #1
Homosexual behavior is not a physiological characteristic like skin or eye color. All behavior is strongly influenced by environmental factors, especially influential people. Identical twins don't have identical experiences, identical thoughts, or identical influences. They don't make identical choices.
The scientific community has not identified a gene for homosexual behavior, just as it has not identified a gene for any type of behavior, though there are behaviors which occur in people with certain genetic disorders, such as Downs Syndrome or Cri du Chat - a disorder which is characterized by loud wailing that sounds cat-like. Children with Autism can be taught behaviors to adapt to their environment rather than remain uncommunicative in social settings.
An extreme behavior disorder, schizophrenia, has a less than 50% occurrence in identical twins, indicating genetics is an influence rather than a cause. Even in a disease strongly influenced by genetics, such as diabetes, environment plays a large role, triggering the onset of the disease.
For gene x to cause behavior y, you must have a 100% occurrence in identical twins.
Homosexuality is a behavioral choice.
2007-10-24 18:33:30 · answer #1 · answered by Lynie 4 · 1⤊ 0⤋
Identical twins are not 100% identical (for example, they do not share the same fingerprints). The fact that they do share the same sexual orientation more than ⅓ of the time does show a correlation to genetics and biology being involved.
A recent scientific study said that researchers have known for years that a man's likelihood of being gay rises with the number of older biological brothers, but the new study found that the so-called "fraternal birth order effect" persists even if gay men were raised away from their biological families. Anthony F. Bogaert, Ph.D., professor at Brock University, said "The research suggests that the development of sexual orientation is influenced before birth."
The older-brother effect was constant regardless of whether the men were raised with natural, adopted or stepbrothers. It also didn't matter if they weren't raised with their biological mothers. If gay younger brothers and older brothers don't have the same home environments, what do they have in common? "They shared the same uterus, the same womb, the same mother," Bogaert said.
Since the study says that the same effect persists if gay men were raised away from their biological families, the only logical conclusion is that environment plays little, if any, role in sexual orientation.
2007-10-18 15:47:54 · answer #2 · answered by χριστοφορος ▽ 7 · 1⤊ 1⤋
Some are probably in the closet, but i bet at least half of the twins are straight. Even though they have the same nature (DNA), nurture has a big affect on sexual orientation. Just because they are reared together doesn't mean they have the same nurture. They have different brains, they process information differently. I'm sure they don't have the exact same friends, or experiences, or like the same activities. A lot of factors determine sexual orientation, and scientists still are not sure exactly how it is determined.
2007-10-18 15:45:42 · answer #3 · answered by Anonymous · 2⤊ 0⤋
No two children in the same family, identical or not, have identical experiences. Nor do identical twins have the same personality. Further, my neighbor's "identical twins" are mirror twins, one is left-brained and right-handed, the other the opposite.
Sorry, your attempt to show that homosexuality is a choice falls to the ground for faulty evidence.
2007-10-18 15:53:05 · answer #4 · answered by Anonymous · 0⤊ 2⤋
Most people think that there is a genetic component of homosexuality, something that makes one more predisposed to it. The exact environmental triggers are unknown as of yet. It's all a moot point anyway, since in any case, gay people didn't choose to be gay. And please find some legitimate sources. And I believe there is still an association between twins raised separately.
2007-10-18 15:43:34 · answer #5 · answered by robert 6 · 0⤊ 2⤋
Think the time they where born. Exactly?No. Which mean in the principle of science "a thing cannot be at the same time." I'm not referring exactly a "thing" but in general sense.
2007-10-19 16:08:47 · answer #6 · answered by arnie 3 · 0⤊ 0⤋
it's early child hood influence, it's self-evident but against the rule, apparently, to discuss
2007-10-18 15:50:14 · answer #7 · answered by Anonymous · 2⤊ 0⤋