Gay gene?

[Kite]

Quote by: Muckraker There are, after all, people who enjoy having sex with, and are sexually attracted to, members of both genders. I can't say their existence favors either side of the argument though.

There are all kinds of things that people are attracted to. Theres people who are attracted to animals, and even inanimate objects. Theres also people who are attracted to anything sexual in general, pansexuals(sp?). I'm not saying that homosexuality has nothing to do with genetic predisposition, I think that it does, but what I'm wondering is if any of these have anything to do with genetic predisposition as well, or are they more a product of environment etc.?

[Tycoon]

Fraternal birth order. The probability that a man has homosexual preference increases with the number of older brothers he has. Each older brother increases the odds by 1/3 – 1/2. This effect cannot have a genetic basis. Speculations for this effect focus on the mother progressively building antibodies against an unknown male protein, more so with each son.

I didn't even know that this actually is a scientific theory. I know a family with four children and the fourth is most definately gay.

[Chancellor]

Quote by: gela Its been argued alot in other threads, but rarely from a scientific viewpoint. Is homosexuality a choice? is it a result of environment? is it purely genetic? Is it a mixutre of all three? Note: This is a scientific debate. Not religious. Things to consider: + true story: A 19 year old girl was kidnapped by a group of men and sexualy assulted by them for three days before she escaped. After this, she became a lesbian; while before it she was hetrosexual. + List of mammals displaying homosexual behavior - Wikipedia, the free encyclopedia + The number of homosexual people seems to have risen as it has became more socialy acceptable [I have no proof for this statement, only a personal observation. Im happy for anyone to either prove or disprove this statement]

While there were a couple of lesbians (who did not know each other and were not in a relationship with each other) that insisted they chose to be lesbians (after I had suggested it was not a choice), I'm not convinced that anyone chooses to be sexually/romantically attracted to another.

I really wish you would have cited a credible source (like this one: MercatorNet - A gay old time in the animal kingdom) and not Wikipedia.

As for the title question of a gay gene:

"Gay gene" researcher Dean Hamer was asked by Scientific American if homosexuality was rooted solely in biology. He replied: "Absolutely not. From twin studies, we already know that half or more of the variability in sexual orientation is not inherited. Our studies try to pinpoint the genetic factors...not negate the psychosocial factors."

Source: "New Evidence of a 'Gay Gene'," by Anastasia Toufexis, Time, November 13, 1995, vol. 146, Issue 20, p. 95.

Something important to understand in this whole gay gene (and, thus, "born that way") theory:

1. Heritable does not mean inherited.

2. Genetics research which is truly meaningful will identify, and then focus on, only traits that are directly inherited.

3. "Associated with" does not mean "caused by."

Almost every human characteristic is in significant measure heritable. But few human behavioral traits are directly inherited, in the manner of height, for example, or eye color. Inherited means "directly determined by genes," with little or no way of preventing or modifying the trait through a change in the environment.

According to a February 7, 1999 Boston Globe article, Ruth Hubbard, a board member of The Council for Responsible Genetics, and the author of Exploding the Gene Myth, said that searching for a gay gene "is not even a worthwhile pursuit...Let me be very clear: I don't think there is any single gene that governs any complex human behavior. There are genetic components in everything we do, and it is foolish to say genes are not involved, but I don't think they are decisive."

[rez]

Quote by: Chancellor According to a February 7, 1999 Boston Globe article, Ruth Hubbard, a board member of The Council for Responsible Genetics, and the author of Exploding the Gene Myth, said that searching for a gay gene "is not even a worthwhile pursuit...Let me be very clear: I don't think there is any single gene that governs any complex human behavior. There are genetic components in everything we do, and it is foolish to say genes are not involved, but I don't think they are decisive."

Nope they are not but they sure are helpful in understanding the question at hand.

homosexuality is more apparent in identical twins, so it does show that shared genes play a role in this.

Population control is a rather silly assessment considering that increase in population plays absolutely no role in how the biology of humans work.

You would think that such a gene would have been selected out of the pool considering the stigma associated with such a trait.

I am of the opinion that gayness has to deal with the biology of the women when she is pregnant in which case it all depends on her hormones and antibodies that are released.

[atheist]

I've taken a biological psychology class, a human sexuality class, and various other psychology classes that have all touched upon this topic. overall, there is no specific "gay gene." there may be genetic things that predispose one to being homosexual, but that does not = a specific gay gene as far as we know.

in terms of prenatal disposition for males (not females), there's one really supported instance in which, with the more sons a woman has, some percentage increases in the chances that her next son will be homosexual (due to the mother's immune system getting sensitized to male proteins progressively with each male birth).

For some women, about half of the girls with Congenital adrenal hyperplasia (an intersex condition in which they are prenatally exposed to androgens) identify themselves as either bi or homosexual. So prenatal exposure to certain hormones can be suspected to play a role in sexuality.

Also, there are three diff. subregions in the brain that have shown differences between het/hom people: the superachiasmatic nucleus, anterior commissure, and specific neurons in the anterior hypothalamus (INAH-3).

One could say, for example, that there's a gene that causes a difference in a certain brain region (which is more identified in homosexuals), which in turn means an increased likelihood of that person being homosexual, but this does not mean that this is a "gay gene".

[loser]

Is homosexuality a choice? is it a result of environment? is it purely genetic? Is it a mixutre of all three?

It's about 90% environment and about 10% genetic. It's mostly learned behavior.

Having six fingers is in fact the dominant gene - but the gene pool is predominately five fingered.

This makes the word "dominant" (and/or it's meaning) meaningless, then.

The Bisexuals. There are, after all, people who enjoy having sex with, and are sexually attracted to, members of both genders. I can't say their existence favors either side of the argument though.

Why stop there? Some people find their sexual gratification in more beastly ways. It's not about sexual attraction, it's about sexual pleasure.

Who you are sexually attracted to is not a choice. It may have some genetic influence but it definitely has cultural influences and environmental influences that I would say overshadow any genetic influences.

It's a learned preference. Experience shapes the sexual outlet.

Why is is that American men are often not sexually attracted to women that don't shave their legs and armpits but many men in other countries are?

Cause American men are pansies and punks and stupid perverts. Give me a woman with a smelly (and hairy) armpit any day! If it's natural, it's the way it should be!

The prime driver of sexual attraction, in my opinion, is culture. Environment also plays a big role in the many cases of abuse, molestation, rape, as well as availability of sexual stimuli in a given environment.

Well, I see there is still a modicum of intelligence left in our world. You are correct, sir.

...everyone certainly has a choice about who they have sex with.

Not as much as we would like to think. Too many are trained from their youth, long before they were able to make choices.

Actually there's a biological reason for that as well. Large breasts biologically imply that as a mother this woman would be much more capable in providing nourishment to our children.

That's a myth and untrue. Breast size has absolutely nothing to do with milk production. Perhaps its the fact that as a woman's breast size increases her manliness decreases. If she has big boobs, she's more likely to be a real woman (well, it used to be that way).

A 52% rate in identical twins and 22% rate in fraternal twins obviously shows that there is a genetic factor in homosexuality.

Actually, it doesn't. It shows that having a twin (especially an identical twin) affects the psychological development of that child. All the twins that I have ever known were a strange lot.

But you don't need the gay gene to be gay.

There is no gay gene.

I'm not saying that homosexuality has nothing to do with genetic predisposition, I think that it does, but what I'm wondering is if any of these have anything to do with genetic predisposition as well, or are they more a product of environment etc.?

I will say it, then. Genetics has virtually nothing to do with sexual preference, it's almost all environment/experience.

homosexuality is more apparent in identical twins, so it does show that shared genes play a role in this.

Or, it could be the shared beds that played the role. People are always too quick to jump the gun and they forget about all of the variables at play.

Population control is a rather silly assessment considering that increase in population plays absolutely no role in how the biology of humans work.

That's wrong. Increases in population often triggers crowded living conditions and its been absolutely proven that population density does indeed affect the biological and genetic conditions of man.

For example, from here Purpose of appendix believed found - CNN.com

"WASHINGTON (AP) -- Some scientists think they have figured out the real job of the troublesome and seemingly useless appendix: It produces and protects good germs for your gut...
...For generations the appendix has been dismissed as superfluous. Doctors figured it had no function. Surgeons removed them routinely. People live fine without them...
... The function of the appendix seems related to the massive amount of bacteria populating the human digestive system, according to the study in the Journal of Theoretical Biology. There are more bacteria than human cells in the typical body. Most are good and help digest food.

But sometimes the flora of bacteria in the intestines die or are purged. Diseases such as cholera or amoebic dysentery would clear the gut of useful bacteria. The appendix's job is to reboot the digestive system in that case.

The appendix "acts as a good safe house for bacteria," said Duke surgery professor Bill Parker, a study co-author. Its location _ just below the normal one-way flow of food and germs in the large intestine in a sort of gut cul-de-sac -- helps support the theory, he said.

Also, the worm-shaped organ outgrowth acts like a bacteria factory, cultivating the good germs, Parker said. That use is not needed in a modern industrialized society, Parker said.

If a person's gut flora dies, it can usually be repopulated easily with germs they pick up from other people, he said. But before dense populations in modern times and during epidemics of cholera that affected a whole region, it wasn't as easy to grow back that bacteria and the appendix came in handy.

In less developed countries, where the appendix may be still useful, the rate of appendicitis is lower than in the U.S., other studies have shown, Parker said.

He said the appendix may be another case of an overly hygienic society triggering an overreaction by the body's immune system."

The complexities of life cause us to miss so many of the unnoticed details.

I am of the opinion that gayness has to deal with the biology of the women when she is pregnant in which case it all depends on her hormones and antibodies that are released.

Gayness is more the product of what the fetus experiences in the womb before birth (mothers often forget or are unaware that their babies hear, see, feel, and generally experience everything in their world while they are carrying them. A baby girl being traumatized right along with her mom as she is beaten by a no-good husband/boyfriend may very well fear and loathe men right from birth. It may appear genetic but it was environmentally learned instead.

in terms of prenatal disposition for males (not females), there's one really supported instance in which, with the more sons a woman has, some percentage increases in the chances that her next son will be homosexual (due to the mother's immune system getting sensitized to male proteins progressively with each male birth). For some women, about half of the girls with Congenital adrenal hyperplasia (an intersex condition in which they are prenatally exposed to androgens) identify themselves as either bi or homosexual. So prenatal exposure to certain hormones can be suspected to play a role in sexuality. Also, there are three diff. subregions in the brain that have shown differences between het/hom people: the superachiasmatic nucleus, anterior commissure, and specific neurons in the anterior hypothalamus (INAH-3). One could say, for example, that there's a gene that causes a difference in a certain brain region (which is more identified in homosexuals), which in turn means an increased likelihood of that person being homosexual, but this does not mean that this is a "gay gene".

Which accounts for my estimate of 10% caused genetically. However, with increasingly invasive techniques used by doctors (including drugs and hormones), these percentages could increase alarmingly.

If the use of drugs such as LSD have been shown to permanently affect the genes of a person, is there any reason not to expect genes to be affected by even more innocuous chemicals, such as lactic acid or adrenaline (epinephrine). I am certain that our genes are in a constant state of flux, mutating endlessly in response to our environs.

[Domino]

This makes the word "dominant" (and/or it's meaning) meaningless, then.

Not at all: it has a very definite meaning, in terms of genetics. The dominant gene will always be expressed instead of the recessive gene. That doesn't mean that there's a lot of dominant genes out there to be expressed. "Dominance" refers to the chance that a carrier of the gene will express it; it does not refer to the proportion of carriers to noncarriers.

[Winter wind]

Quote by: loser It's about 90% environment and about 10% genetic. It's mostly learned behavior.

No it's 100% genetic!

erm...what I was getting at is I need proof.

Why stop there? Some people find their sexual gratification in more beastly ways. It's not about sexual attraction, it's about sexual pleasure.

so bisexual people can't love? It is impossible for a homosexuals to love?

Proof it.

Actually, it doesn't. It shows that having a twin (especially an identical twin) affects the psychological development of that child. All the twins that I have ever known were a strange lot.

fair enough. except the twins I know are normal. A much better argument is that the twins are more likely to apply for this survey if they are gay.

[loser]

Quote: Quote by: loser It's about 90% environment and about 10% genetic. It's mostly learned behavior. No it's 100% genetic! erm...what I was getting at is I need proof.

Asking homosexuals is not going to provide proof because they can rarely be objective. Psychology has taught us that traumatic experiences are often repressed in memory. If a child was sexually abused when an infant, it's extremely likely those memories have been blocked. Therefore, if abuse was the factor for that individual being gay, it might not ever be revealed. In fact, it is more likely to be attributed to something else such as genetics (i.e., "I was born that way"). This also applies to the womb trauma that I mentioned previously. The individual will not have a conscious memory of those events.

The proof is there for those willing to see it. The breakup of the traditional family has had enormous effect on the sexual development of children. Step-parents are often sexually attracted to their step-children, resulting in sexual abuse. Absent fathers (no male role model) cause sexual dysfunction in children. Physically abusive parents/step-parents cause sexual dysfunction. Too many other nurturing abnormalities to mention also result in sexual dysfunction.

I didn't just pull these ideas out of a hat. They have been scientifically (and socially) proven. Do a little research, observe various family structures, talk to those affected by their environment, and see what conclusions you can draw without my input. I think you'll be forced to agree with me if you are honest with yourself.

Quote: Why stop there? Some people find their sexual gratification in more beastly ways. It's not about sexual attraction, it's about sexual pleasure. so bisexual people can't love? It is impossible for a homosexuals to love? Proof it.

Love has absolutely nothing to do with it. Anyone can love. We're not talking about love, we're talking about lust (desire). Sexual attraction is not based on love. Lust is often confused for love. They are totally different. A woman may love her dog but if she is sexually attracted to it, that is lust.

Actually, it doesn't. It shows that having a twin (especially an identical twin) affects the psychological development of that child. All the twins that I have ever known were a strange lot. fair enough. except the twins I know are normal. A much better argument is that the twins are more likely to apply for this survey if they are gay.

I was being flippant when I said all of the twins that I knew were strange. All the ones that I knew, I only knew casually...I'm hardly capable of making a deep psychological evaluation of twins. My point was that the bond between identical twins is usually much stronger than regular siblings and they are even treated differently. The increased incidence of homosexuality in identical twins could very well be based on this unique bond and closeness growing up. It's not just genetics that make identical twins different from others.

Am I making more sense now?

[Jack]

Asking homosexuals is not going to provide proof because they can rarely be objective.

If that's the case then asking anyone about their subject experiences cannot reveal objective realities. I think if you extend that argument a bit you'll see where it breaks down. Besides, psychology can't offer proofs about sexual orientation, only indicators and possibilities.

Homosexuals themselves may not be able to provide objective proof, but by relating their experiences as best they can recall them, and by aggregating those responses over time, we can begin to build a better understanding as to the beginnings of their awareness of their orientation. We follow the evidence to form a conclusion. I doubt we'll ever have conclusive proof of where orientation begins, gay or straight. There are simply too many factors involved.

[Tycoon]

The proof is there for those willing to see it. The breakup of the traditional family has had enormous effect on the sexual development of children. Step-parents are often sexually attracted to their step-children, resulting in sexual abuse. Absent fathers (no male role model) cause sexual dysfunction in children. Physically abusive parents/step-parents cause sexual dysfunction. Too many other nurturing abnormalities to mention also result in sexual dysfunction.

You can't base your entire argument around this. I'm gay and none of the said things occured in my life.

[another day]

Quote by: gela Well, it shows that homosexuality doesn't need a 'gay gene' to exist, because the adoptive brothers are still homosexual. But it also shows that genes still play a part, through the twins thing. That basicly answeres it. Genes can help homosexuality along. But you don't need the gay gene to be gay.

No..very few of the adoptive ones were gay. Those few may have been ones that inherited it from their biological parents.

[Chancellor]

Quote by: Isherwood If that's the case then asking anyone about their subject experiences cannot reveal objective realities. I think if you extend that argument a bit you'll see where it breaks down. Besides, psychology can't offer proofs about sexual orientation, only indicators and possibilities.

Subjective experiences cannot reveal objective realities.

Homosexuals themselves may not be able to provide objective proof, but by relating their experiences as best they can recall them, and by aggregating those responses over time, we can begin to build a better understanding as to the beginnings of their awareness of their orientation. We follow the evidence to form a conclusion. I doubt we'll ever have conclusive proof of where orientation begins, gay or straight. There are simply too many factors involved.

And not one of them will ever be able to tell you how they experienced a particular gene (or combination of genes) actually causing their homosexuality. Not one of them will ever be able to tell you what they experienced in the womb that caused them to be born sexually/romantically attracted to others of their own sex.

[Rainbow]

Quote by: gela Gay gene ? Is homosexuality a choice? is it a result of environment? is it purely genetic? Is it a mixutre of all three? Things to consider: + true story: A 19 year old girl was kidnapped by a group of men and sexualy assulted by them for three days before she escaped. After this, she became a lesbian; while before it she was hetrosexual. + List of mammals displaying homosexual behavior - Wikipedia, the free encyclopedia + The number of homosexual people seems to have risen as it has became more socialy acceptable.

#1
Psychology related case.

#2
Not sufficient data to determine animals behaviour.

#3
It carries variety of reasons.

Is homosexuality a choice? is it a result of environment? is it purely genetic? Is it a mixutre of all three?

Genetics stands for a very low number.
It could be one and/or a mixture of elements.

[Chancellor]

Quote by: rez Nope they are not but they sure are helpful in understanding the question at hand.

Not really.

homosexuality is more apparent in identical twins, so it does show that shared genes play a role in this.

"Gay gene" researcher Dean Hamer was asked by Scientific American if homosexuality was rooted solely in biology. He replied: "Absolutely not. From twin studies, we already know that half or more of the variability in sexual orientation is not inherited. Our studies try to pinpoint the genetic factors...not negate the psychosocial factors."

Population control is a rather silly assessment considering that increase in population plays absolutely no role in how the biology of humans work.

Agreed.

You would think that such a gene would have been selected out of the pool considering the stigma associated with such a trait.

Stigma is a purely cultural construct - biology has nothing to do with it.

I am of the opinion that gayness has to deal with the biology of the women when she is pregnant in which case it all depends on her hormones and antibodies that are released.

Well, since there is no testing that can be performed on pregnant women to confirm this, it's nothing more than speculation - just like the view that homosexuality is purely a matter of personal choice.

[atheist]

Question:

How many people in this thread have taken a college/university level class that touched upon the subject of homosexuality at a biological level?

If yes, what is your opinion on this topic?

[Rainbow]

Quote by: atheist Question: How many people in this thread have taken a college/university level class that touched upon the subject of homosexuality at a biological level? If yes, what is your opinion on this topic?

What is : college/university level class ; biological level ?
Does it mean : faculty of Biology is not the main subject ?

Are you conducting some poll, inquiry, questionnaire, etc. ?