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Group of Scientists Believe They Have Unlocked Hereditary Question of Why People are Gay

A group of scientists from the National Institute for Mathematical and Biological Synthesis say they believe they have the answer to why people are gay, and believe it is an "epigenetic" one linking fathers to lesbian daughters and mothers to gay sons. And they say they can prove whether their theory is right within six months, US News reports:

GenomeLong thought to have some sort of hereditary link, a group of scientists suggested Tuesday that homosexuality is linked to epi-marks — extra layers of information that control how certain genes are expressed. These epi-marks are usually, but not always, "erased" between generations. In homosexuals, these epi-marks aren't erased — they're passed from father-to-daughter or mother-to-son, explains William Rice, an evolutionary biologist at the University of California Santa Barbara and lead author of the study.


Rice and his team created a mathematical model that explains why homosexuality is passed through epi-marks, not genetics. Evolutionarily speaking, if homosexuality was solely a genetic trait, scientists would expect the trait to eventually disappear because homosexuals wouldn't be expected to reproduce. But because these epi-marks provide an evolutionary advantage for the parents of homosexuals: They protect fathers of homosexuals from underexposure to testosterone and mothers of homosexuals from overexposure to testosterone while they are in gestation.

"These epi-marks protect fathers and mothers from excess or underexposure to testosterone — when they carry over to opposite-sex offspring, it can cause the masculinization of females or the feminization of males," Rice says, which can lead to a child becoming gay. Rice notes that these markers are "highly variable" and that only strong epi-marks will result in a homosexual offspring.

Adds Rice: "We've found a story that looks really good. There's more verification needed, but we point out how we can easily do epigenetic profiles genome-wide. We predict where the epi-marks occur, we just need other studies to look at it empirically. This can be tested and proven within six months. It's easy to test. If it's a bad idea, we can throw it away in short order."

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  1. So certain "epi-marks" are retained in gay people when ordinarily they're not passed on, affecting how genes are expressed even with normal hormonal exposure. The retention of epi-marks is obviously not restricted to gay people, just those that affect sexual orientation.

    This is so far only a modeled hypothesis with no direct evidence. And it's probably too simplistic. After their discovery, sex researchers hypothesized that a prevalent imbalance of sex hormones were responsible for sexual orientation. Gay men would be treated with testosterone in vain.

    Posted by: Kyle | Dec 11, 2012 3:34:55 PM

  2. "Evolutionarily speaking, if homosexuality was solely a genetic trait, scientists would expect the trait to eventually disappear because homosexuals wouldn't be expected to reproduce. But because these epi-marks provide an evolutionary advantage for the parents of homosexuals: They protect fathers of homosexuals from underexposure to testosterone and mothers of homosexuals from overexposure to testosterone while they are in gestation."

    That is a badly-written pieces of text.

    How would a father of [a homosexual fetus] be underexposed to testosterone [when the mother is carrying said fetus]?

    Posted by: Drummond | Dec 11, 2012 3:35:49 PM

  3. This sounds like a partial theory to explain some gays and lesbians, but not all.

    Posted by: anon | Dec 11, 2012 3:37:59 PM

  4. WTF is this ?
    "Feminization of males; masculization of females"........

    Is this Victorian phrenology ?
    If these guys are starting out their research from such a primitive understanding of what gay is , then the results of their "study" will be garbage.

    "Feminization of males" that what is supposed to have made me gay ?
    Seriously ?
    Gays are "feminized" ? Seriously ?
    You guys need to get out more.
    Where is RICK when i need him ?

    Posted by: JackFknTwist | Dec 11, 2012 3:40:22 PM

  5. I'd wait after the next 6 months to say something categorical about this, but it's another step in the direction that puts an end to the "people choose to be gay" nonsense. And in turn, another step in the direction to destroy ex-gay therapy and homophobic lies.

    Posted by: Francis | Dec 11, 2012 3:42:14 PM

  6. @FRANCIS Or maybe the end of homosexuality...

    Posted by: calvin | Dec 11, 2012 3:44:41 PM

  7. Yeah, we need to watch where this study is going and taking is.

    And should this study prove uncannily accurate we must agitate that there must never never be an ante-natal test developed.

    We all know where that would be going !

    Posted by: JackFknTwist | Dec 11, 2012 3:53:55 PM

  8. This is just a further exploration of the epigenetics of human sexuality. It's a more focused and engaging question for these scientists to study and continue studying. A 2004 study found homosexuality was passed on epigenetically through the mother only. It's interesting that they're bringing the father into this study. "maternal loading of transmission of sexual orientation could indicate epigenetic factors." I wouldn't mind being a part of further study.

    Posted by: CD | Dec 11, 2012 3:58:53 PM

  9. No, really not a good idea. That's all the hateful people in this world need - a method of how to wipe us out. I wonder how pro-life these wackos will be then.

    Posted by: Jack M | Dec 11, 2012 3:59:46 PM

  10. Some guys aren't quite understanding "masculinization" and "feminization" correctly. These are probably inappropriate rubrics, but what researchers mean by them is that attraction to men likely has an identical or related etiology in gay/bi men and straight/bi women alike and that the attraction is restricted to women in ordinary or archetypal development. (And the inverse for attraction to women.) This is a reasonable assumption.

    When a definitive explanation of homosexuality is offered, you probably won't see these terms anymore but very specific descriptions instead.

    Posted by: Kyle | Dec 11, 2012 4:01:16 PM

  11. The chances of that happening Calvin, are basically zero. There are simply too many factors that are in play to categorically prove a child being gay or straight in the womb. Then you have bisexuals, transsexuals, and we can go down the list.

    It is what it is. I don't particularly care for the science because I don't like our lives being under such a microscope, but again, we'll see where this goes in 6 months, and without the "gay is a choice" card, homophobes aren't left with much but blind hatred.

    Posted by: Francis | Dec 11, 2012 4:01:29 PM

  12. u wanna read something real funny - go to the US news reports link on top of article and see comments left by people via facebook - all the anti-gays are from Red states...loser states, and or BuyBULL thumpers.....I love giving them a hard time back on facebook - the assholes that they are.....

    Posted by: Disgusted American | Dec 11, 2012 4:08:07 PM

  13. Don't read too much into "feminization" or "masculinizing." They don't mean it as "flouncing around in a dress" or whatever, but in a much broader way.

    Exposure to hormones in utero has long been suggested as one possible reason why people are gay. That's what all those studies about ring-finger length, the directionality (clockwise or counterclockwise) of hair 'whorls' and brain structure are really all about- exposure to hormones during gestation that leave very subtle physical clues.

    Posted by: Caliban | Dec 11, 2012 4:22:30 PM

  14. Feminized men are all gay, and all gay men are feminized? And what about bi males, them too?

    I'm gay,as gay as any other gay male, and am not the least feminized. This theory is flawed.

    Although there's no question about a genetic marker for rigid homosexuality IMO. And I think most humans sexuality is somewhat fluid and variable.

    Posted by: ratbastard | Dec 11, 2012 4:42:09 PM

  15. Folks, it is high damn time we atarted objecting to every research idea the goal of which is to find a "cause" for homosexuality, which implies that there is something WRONG or UNNATURAL about same-sex attraction.

    Does anybody, after all, ask what the "cause" of heterosexuality is? No, because it is just considered to be a natural part of the human condition. So to constantly be seeking a "cause" of homosexuality is to be seeking an explanation for a "mal-function" of some sort.

    And for those of you who misguidedly believe that if a biological "cause" of same-sex attraction were discovered, all our problems would be solved since our sexuality could no longer be attributed to "choice", think again. People's hostility to homosexuality is emotional in nature, not rational, so such a finding would be worthless.

    Of course any such attempt to find a "cause" is doomed to failure since human sexuality is complex and varied and comes in 1000 shades of gray, with the vast majority of individuals having at least some attraction to both genders....a fact that is well-established.

    This is therefore not "science", but an attempt to isolate "homosexuality" and put it in a box that will make it easy to "deal with" just as the idea of a black/white paradigm of "gay"/"straight" is designed to do, much to the detriment of us all.

    I am really sick and tired of the basic premises of this kind of "study" and we should begin objecting to them as strenuously as we object to the idea of "gay conversion therapy" because they are both rooted in the same mindset.

    Posted by: Rick | Dec 11, 2012 4:46:06 PM

  16. If this information is accurate, and ever becomes useful, then we'll be able to make people gay. Good for us. Good for the planet. Bigots think they'll wipe us out, but they should be very scared.

    Posted by: Randy | Dec 11, 2012 4:59:02 PM

  17. Why do gay men flip out at the word feminization??? It's been proven many of our inners to brain or inner ear are feminized. Big deal.

    Secondly, and more importantly, this theory proves what I always thought. It is definitely my mothers doing.....

    Posted by: Michael | Dec 11, 2012 5:08:12 PM

  18. "Why do gay men flip out at the word feminization??? "

    Because we are men, not women. I realize that is a foreign concept to those of you who suffer from psychological gender-confusion and have no real male identity--which no doubt accounts for your being perplexed--but most of us do have male identities.

    "It's been proven many of our inners to brain or inner ear are feminized. Big deal."

    No, it has not. Stop spreading lies for the purpose of trying to drag those of us who are characterized by normal masculinity down into your gender-confused hole. Thanks.

    Posted by: Rick | Dec 11, 2012 5:14:11 PM

  19. " can cause the masculinization of females or the feminization of males."

    Yup, that right there makes the whole thing look idiotic.

    Seriously, considering how many incredibly butch gay men I know that are construction workers, steel workers, police men, etc... this entire premise seems pathetic.

    Posted by: johnny | Dec 11, 2012 5:18:41 PM

  20. Whatever happened to the lack-of-androgen-in-utero-theory? It allowed for a lot more variation...

    Posted by: drumstick | Dec 11, 2012 5:19:18 PM

  21. I find this interesting. I wouldn't be placing all my money on it of course, but I am interested in the idea of "nature's" role in sexuality. This may be because I have studied sciences my entire life, so the quest for answers never really ends for people like me. :)

    Anyways, I found this article, which I personally felt did a better job explaining things down to my level. Check it out if you like.

    Side Note: It does explain in this article that "feminization/masculinization" is meant in the terms of sexual orientation and NOT physical appearances or social constructs on the idea of what "feminine" means.

    Posted by: AndyN | Dec 11, 2012 5:21:11 PM

  22. "It does explain in this article that "feminization/masculinization" is meant in the terms of sexual orientation "

    Oh, well that clears things right up, doesn't it? Are these presumably heterosexual eggheads aware of the existence of tops and aware that without tops there can be no bottoms? And that it is much more challenging to "take" another man than it is to take a weak, little woman?

    And are they aware that most gay men have had sex with a woman at least once, including some who esclusively bottom when they are with men?

    The more anyone tries to defend this garbage, the more ridiculous the entire enterprise appears.

    Posted by: Rick | Dec 11, 2012 5:25:30 PM

  23. The scientists can't even answer the question why most people are straight. Is there a "straight" gene?

    Posted by: simon | Dec 11, 2012 5:39:01 PM

  24. You guys need to be careful, I've read through the comments and many of you are taking terms that are meant to be understood in a biological context and attaching a colloquial meaning to them. "Masculinization" and "feminization" does not mean you play more sports or speak with a lisp; it is referring to the biological process by which the sexes are differentiated and developed during maturation. These two terms are simply the shorthand titles for these processes.

    This study does not claim to have found the "gay gene", nothing could be further from the truth. The very branch of this study, "epigenetics", which refers to the expression of genes in ways that does not alter the actual genetic sequence in DNA, should make that obvious to anyone with a basic knowledge in biology.

    When we discuss DOMA or Prop 8 on this site, I accept that I am not an expert in the field of law. While I approach everything with a level of skepticism, I also accept that Mr. Waldman has a greater understand of the subject than I do. If something doesn't add up, I give him the benefit of the doubt and ask him a question, rather than jumping to wild conclusions.

    The same needs to be done here. The great majority of us here are not biologists. Don't start tossing around accusations before you truly understand what's happening.

    Posted by: Moony | Dec 11, 2012 6:12:35 PM

  25. But what about the majority of us gays who are masculine? Feminine gays are usually the ones who get the media attention but I believe that most of us are masculine. I, nor my partner have any feminine traits but I loves me a man!

    Posted by: ToThePoint | Dec 11, 2012 6:17:43 PM

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