Obamacare: Eugenics

[OldTrapper]

J Abnorm Psychol. 1996 Aug;105(3):440-5.

Is homophobia associated with homosexual arousal?
Adams HE, Wright LW Jr, Lohr BA.

Department of Psychology, University of Georgia, Athens 30602-3013, USA.

The authors investigated the role of homosexual arousal in exclusively heterosexual men who admitted negative affect toward homosexual individuals. Participants consisted of a group of homophobic men (n = 35) and a group of nonhomophobic men (n = 29); they were assigned to groups on the basis of their scores on the Index of Homophobia (W. W. Hudson & W. A. Ricketts, 1980). The men were exposed to sexually explicit erotic stimuli consisting of heterosexual, male homosexual, and lesbian videotapes, and changes in penile circumference were monitored. They also completed an Aggression Questionnaire (A. H. Buss & M. Perry, 1992). Both groups exhibited increases in penile circumference to the heterosexual and female homosexual videos. Only the homophobic men showed an increase in penile erection to male homosexual stimuli. The groups did not differ in aggression. Homophobia is apparently associated with homosexual arousal that the homophobic individual is either unaware of or denies.

PMID: 8772014 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/pubmed/8772014?dopt=Citation

As has been shown in many studies, it is the fear of being homosexual that usually drives homophobic men.

See how you twist things in your twisted mind? First you lie by saying I hate homosexuals, and when you see that won't work then you drag up some twisted study, and try to make the claim that I am a latent homosexual which drives my homophobia.

In your degenerate mind it could never be about morals, or values.

Now, I answered your question about your proof of a genetic connection to homosexuality, and as I have said all along there is no such proof, and that I believe it is more psychological then any other. However, you cannot accept that so you drag up another strawman to avoid answering the question I ask.

It is really quite the same as your constant mentioning that you do not believe I have a Doctorate of Theology based on your lack of knowledge of the Bible, and your constant attempts to denigrate the scripture, and my refusal to engage in your endless incompetent dissertations regarding such.

 

[Sihouette]

Forgive Mare, he is a bit of a drama queen.

I can't believe a debate about abortion has turned into him accusing yet another poster of being a latent homosexual because they disapprove of his sexual fetish.

*sigh*

I still think that if you're going to mandate the birth of each pregnancy [fetus] based on the belief that no man may arbitrarily decide when that fetus' growth resembles a human...that you cannot then walk the other side of the fence and say when that fetus passes through the birth canal and continues to develop until about age 23, that it is "on it's own" without the vital care necessary to sustain it to the end of its true development.

I'll bet these are the same hypocrites who don't care to mandate free prenatal care or intensive care for premies. It's not that they support life, it's that they support subjegation of women.

Think about it..they really don't give a crap if the child lives or dies...evidenced by their refusal to chip in for women who CANNOT provide for the child upon its birth, or even before [drug addicted]..

 

[Mare Tranquillity]

See how you twist things in your twisted mind? First you lie by saying I hate homosexuals, and when you see that won't work then you drag up some twisted study, and try to make the claim that I am a latent homosexual which drives my homophobia.

In your degenerate mind it could never be about morals, or values.

Now, I answered your question about your proof of a genetic connection to homosexuality, and as I have said all along there is no such proof, and that I believe it is more psychological then any other. However, you cannot accept that so you drag up another strawman to avoid answering the question I ask.

It is really quite the same as your constant mentioning that you do not believe I have a Doctorate of Theology based on your lack of knowledge of the Bible, and your constant attempts to denigrate the scripture, and my refusal to engage in your endless incompetent dissertations regarding such.

You don't answer my questions, but I try to answer yours. You have demanded over and over again that I provide PROOF that being gay is genetic and I can't do that, all I can do is what science can do and that is provide you with evidence. Since almost all that evidence is for a genetic basis, then one can suspect that there is a genetic basis for it.

I didn't accuse you of anything in my last two posts, I put those up because they were interesting and they suggest that homophobia and bigotry may have causes that many people don't want to look at. If you think everything I post applies to you, then your ego is even bigger than I thought.

You have claimed to have a Doctorate in Theology, but you have not supplied any proof of that nor have you shown yourself to be any kind of Biblical scholar. Why don't you tell us about where you got your Doctorate?

You have called me names in almost every post, you have accused me of perverting scripture, but you have never given even a single example of that. At least when I correct your religious posts I always give chapter and verse to prove my point.

 

[Mare Tranquillity]

I still think that if you're going to mandate the birth of each pregnancy [fetus] based on the belief that no man may arbitrarily decide when that fetus' growth resembles a human...that you cannot then walk the other side of the fence and say when that fetus passes through the birth canal and continues to develop until about age 23, that it is "on it's own" without the vital care necessary to sustain it to the end of its true development.

I'll bet these are the same hypocrites who don't care to mandate free prenatal care or intensive care for premies. It's not that they support life, it's that they support subjegation of women.

Think about it..they really don't give a crap if the child lives or dies...evidenced by their refusal to chip in for women who CANNOT provide for the child upon its birth, or even before [drug addicted]..

Well, at least we agree on abortion.

 

[Mare Tranquillity]

The Washington Blade
http://www.washingtonblade.com/
No fear factor in 'homophobia,' study claims
Researchers say anti-gay prejudice rooted in disgust, 'contamination' concerns...

There you have it: fear of contamination, also fear of it being contagious, and fear of being perceived as being gay and thus in danger of being beaten or killed by other fearful people.

Even your own citations disagree with your position.

 

[Mare Tranquillity]

Forgive Mare, he is a bit of a drama queen.

I can't believe a debate about abortion has turned into him accusing yet another poster of being a latent homosexual because they disapprove of his sexual fetish.

I'm sure that you will enjoy our Doctor of Theology's post from Discover magazine. Doctor couldn't understand it and like you didn't realize that it directly contradicted his position (and yours), but it's still useful.

Despite the disagreement between the researchers, the fact remains that the twin studies have demonstrated a clear genetic basis for homosexual orientation and they have (as noted in the article) that the environment has been ruled out as a cause of homosexuality in men.

From your Discover article here is a quote:
"Whether or not a gay gene, a set of gay genes, or some other biological mechanism is ever found, one thing is clear: The environment a child grows up in has nothing to do with what makes most gay men gay. Two of the most convincing studies have proved conclusively that sexual orientation in men has a genetic cause.

William Reiner, a psychiatrist at the University of Oklahoma Health Sciences Center, explored the question of environmental influences on sexuality with a group that had been surgically shifted from boys to girls. These boys had been born with certain genital deformities; because it is easier to fashion a vagina than a penis, the boys were surgically made into girls at birth. In many cases they were raised as girls, kept in the dark about the surgery, and thought themselves female long into adulthood. Invariably, Reiner found that the faux females ended up being attracted to women. If societal nudging was what made men gay, at least one of these boys should have grown up to be attracted to men. There is no documented case of that happening.

The second study was an examination of twins by psychologist Michael Bailey of Northwestern University. Among identical twins, he found that if one was gay, the other had a 50 percent chance of also being gay. Among fraternal twins, who do not share the same DNA, there was only a 20 percent chance.


At first glance, those results seem to suggest that at least some homosexuality must not be genetic. Identical twins have the same genes, right? How could one turn out gay and the other not gay as often as 50 percent of the time? There are many other traits that are not always the same in identical twins, however, like eye color and fingerprints. The interesting question is, how do any of these major differences arise between two products of the same code?

The solution to that question is exactly what Bocklandt is trying to find. By looking not at DNA but at where DNA is switched off, he hopes to find the true genetic seat of homosexuality. Hamer looked at broad regions of chromosomes using genetic markers, a low-resolution result that tells little more than “something’s going on somewhere around here.” Bocklandt is hoping to look with a much stronger magnifying glass at the areas Hamer’s research *highlighted. If he succeeds, it will be a triumph not only for the genetics of homosexuality but also for genetic research in general.

Bocklandt has collected DNA from two groups of 15 pairs of identical twins. In one group, both twins are gay. In the second, one twin is gay, and the other is straight. Identical twins have the same DNA, but the activity of their genes isn’t necessarily the same. The reason is something called methylation."

The trick when posting a link is to actually READ the article, Siho didn't do it either and she posted several articles contradicting her own thesis.

 

[Mare Tranquillity]

I'm curious about something, Siho. You claim that gay people are made gay by gay people "programming" them just like you do with the poor beleaguered animals, right?

How many children have you personally done this to? Any? Can you cite any examples of ANYONE you can prove has done this successfully? If so, have you reported them to the police?

I think that if you have no proof of this being done by anyone, then you are probably making it up to fulfill some need of your own. Put up or shut up.

 

[OldTrapper]

I'm sure that you will enjoy our Doctor of Theology's post from Discover magazine. Doctor couldn't understand it and like you didn't realize that it directly contradicted his position (and yours), but it's still useful.

Despite the disagreement between the researchers, the fact remains that the twin studies have demonstrated a clear genetic basis for homosexual orientation and they have (as noted in the article) that the environment has been ruled out as a cause of homosexuality in men.

From your Discover article here is a quote:
"Whether or not a gay gene, a set of gay genes, or some other biological mechanism is ever found, one thing is clear: The environment a child grows up in has nothing to do with what makes most gay men gay. Two of the most convincing studies have proved conclusively that sexual orientation in men has a genetic cause.

No Mare, the "trick" is to not limit your "research" to that which supports your position, to dig deeper.

In the excerpt from Discover you chose to post you ignore the part where it says "Whether or not a gay gene, a set of gay genes, or some other biological mechanism is ever found,...." Notice how you, and writer himself, ignores that little comment of "other biological". You, like him, completely ignore the very conclusion he comes to.

Now, here are some newer research articles you would not want to read simply because they do not support your belief.

Environmental factors may influence sexual orientationOct 26, 2006 ... It is the first study to examine an entire group of homosexuals for environmental factors in their decisions to marry homosexually. ...
http://www.lifesitenews.com/ldn/2006/oct/06102608.html

Homosexual behavior due to genetics and environmental factorsJun 28, 2008 ... Homosexual behavior is largely shaped by genetics and random environmental factors, according to findings from the world's largest study of ...
http://www.eurekalert.org/pub_releases/2008-06/qmuo-hbd062608.php

Homosexuality: A Christian Perspective - What Causes Homosexuality?This study confirms my understanding that the cause of homosexuality is a highly complex combination of various factors, some genetic and some environmental ...
http://www.ccel.org/contrib/exec_outlines/hom/hom_04.htm


Now, you attempt to do theame thing in all of your arguments. Like when you made the claim that David, and Jonathen, were homosexuals. I showed that to be a lie, yet you refused to accept it wanting to denigrate the Bible, and Christian beliefs. The same was true of all else you brought up till I tired of your doublespeak, and quit. The you cast dispersions on my Doctorate.

Another tactic you use is the one in the previous post where you insinuate that I am a latenet homosexual. Ever since this topic began you have accused me of hating homosexuals all the while refusing to acknowledge the harm homosexuality has done to society especially in the area of the transmission of HIV/AIDS ever since the late 50's, and in other areas.

Then you post an article about homophobes being latent homosexuals, and then when called on it you lie, and say it was just an article of "interest".

That is your form of "debate" which is reflective of your entire life, and lifestyle. One of denial, lies, and attempts to justify your own perversion by casting doubts on others. And when called on it you simply try to reflect your attitude onto others.

Try a little honest self reflection. You will be a better person for it.

 

[Mare Tranquillity]

Environmental factors may influence sexual orientationOct 26, 2006 ... It is the first study to examine an entire group of homosexuals for environmental factors in their decisions to marry homosexually. ...
http://www.lifesitenews.com/ldn/2006/oct/06102608.html

Interesting, but I'd like to see it duplicated. The small town vs big city difference has been studied and noted before and the conclusion was that in small towns the social pressure was so much greater that gays tended to stay closeted and married heterosexually to please parents.

Homosexual behavior due to genetics and environmental factorsJun 28, 2008 ... Homosexual behavior is largely shaped by genetics and random environmental factors, according to findings from the world's largest study of ...
http://www.eurekalert.org/pub_releases/2008-06/qmuo-hbd062608.php

This was my favorite, right there in the title: GENETICS AND ENVIRONMENTAL FACTORS. I have written many times about the effect of chemicals on the human body--especially the fetal development period--where things like dioxin and polychlorinated biphenyls have been shown to cause sexual and gender changes. So once again you are supporting my position.

Homosexuality: A Christian Perspective - What Causes Homosexuality?This study confirms my understanding that the cause of homosexuality is a highly complex combination of various factors, some genetic and some environmental ...
http://www.ccel.org/contrib/exec_outlines/hom/hom_04.htm

If even the Bible-beaters admit that it is a complex issue based in genetics and environtmental factors WHY ARE YOU PERSECUTING THESE PEOPLE? Genetics and environmental factors are NOT bad lifestyle choices.

 

[Mare Tranquillity]

Now, you attempt to do theame thing in all of your arguments. Like when you made the claim that David, and Jonathen, were homosexuals. I showed that to be a lie, yet you refused to accept it wanting to denigrate the Bible, and Christian beliefs. The same was true of all else you brought up till I tired of your doublespeak, and quit. The you cast dispersions on my Doctorate.

You have made a very hollow claim to a Doctorate with no proof or substantiating information. You have exhibited a cowardly attitude in that you wil not answer questions. You expressed YOUR OPINION about David and Jonathan, but you refused to answer when I questioned when you had last stripped naked and sworn love for a male friend, and when you had laid on the ground kissing your male friends, or had said that your male friend's love surpassed that of women. If you cannot support your opinion why should I accept it?

Another tactic you use is the one in the previous post where you insinuate that I am a latenet homosexual. Ever since this topic began you have accused me of hating homosexuals all the while refusing to acknowledge the harm homosexuality has done to society especially in the area of the transmission of HIV/AIDS ever since the late 50's, and in other areas.

You may well be a latent homosexual or a repressed bi-sexual since you exhibit many of the attributes that science has identified as being markers thereof. I have discounted your "harm" arguments because they are a double standard. You have not addressed the much larger harm caused by the heterosexual population but instead choose to focus on the people you don't like. Lenin, Pol Pot, Mao, Stalin, Saddam, Mussolini, Hitler, Ted Bundy, Ed Gein, Gacy, and Dick Cheney are all heterosexuals, you can't name a single war started by homosexual people, but lots of them have been started by Christians. You have ignored the fact that millions and millions of babies have been aborted by heterosexuals and none by gays, you ignore the fact that lesbians have less AIDS and venereal disease than any other group. You insist on bashing GAY MEN, a tiny minority you don't like for reasons that remain obscure since they aren't doing nearly as much damage as some of the people you do like. You are SUCH a hypocrite around this subject that it makes me suspect that you have something to hide.

Then you post an article about homophobes being latent homosexuals, and then when called on it you lie, and say it was just an article of "interest".

What makes it a "lie"? It was interesting in light of your behavior. Got guilt?

That is your form of "debate" which is reflective of your entire life, and lifestyle. One of denial, lies, and attempts to justify your own perversion by casting doubts on others. And when called on it you simply try to reflect your attitude onto others.

What's weird is that you don't know anything about my entire life or lifestyle. You also have not proved any perversion on my part--that's just another one of your tasty rectal reclamations I guess, since you have provided not a single shred of proof.

 

[Mare Tranquillity]

Dig deep the man said, how deep?

“The asymmetry was not seen in straight women and gay men.
And building on earlier imaging research showing different patterns of brain activation between the sexes in response to emotional stimuli, the Swedish researchers showed that certain activation patterns for gay men and women tended to more closely resemble those of the opposite sex than their own.
The Brain and Sex
While earlier brain imaging studies have shown differences in brain activation between gay and straight men and women when measuring sexual attraction, the study is among the first to show the differences in areas unrelated to sexuality.
"This and other research seems to be sending the same message, which is that sexual orientation is part of a package. It is not an isolated trait," says neuroscientist Simon LeVay, PhD, who has long studied sexuality and the brain.
In 1991, LeVay was among the first to identify differences in the brains of homosexual and heterosexual people when his research identified a small region of the hypothalamus that was larger in straight men than in women and gay men.
Among other things, the hypothalamus is involved with regulating sexual response.”
http://www.webmd.com/brain/news/20080616/gay-brain-shows-gender-atypical-traits

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Hum Genet. 2006 Feb;118(6):691-4. Epub 2005 Dec 21.
Extreme skewing of X chromosome inactivation in mothers of homosexual men.
Bocklandt S, Horvath S, Vilain E, Hamer DH.
Department of Human Genetics, University of California-Los Angeles, Los Angeles, CA, USA. sbocklandt@mednet.ucla.edu
Human sexual preference is a sexually dimorphic trait with a substantial genetic component. Linkage of male sexual orientation to markers on the X chromosome has been reported in some families. Here, we measured X chromosome inactivation ratios in 97 mothers of homosexual men and 103 age-matched control women without gay sons. The number of women with extreme skewing of X-inactivation was significantly higher in mothers of gay men (13/97=13%) compared to controls (4/103=4%) and increased in mothers with two or more gay sons (10/44=23%). Our findings support a role for the X chromosome in regulating sexual orientation in a subgroup of gay men.
PMID: 16369763 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/16369763

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Invest Clin. 2009 Sep;50(3):377-91.
[Influence of genetic factors on human sexual orientation. Review]
Rodríguez-Larralde A, Paradisi I.
Laboratorio de Genética Humana, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, (IVIC), Caracas, Venezuela. arodrigu@ivic.ve
Human sexual orientation is a complex trait, influenced by several genes, experiential and sociocultural factors. These elements interact and produce a typical pattern of sexual orientation towards the opposite sex. Some exceptions exist, like bisexuality and homosexuality, which seem to be more frequent in males than females. Traditional methods for the genetic study of behavior multifactorial characteristics consist in detecting the presence of familial aggregation. In order to identify the importance of genetic and environmental factors in this aggregation, the concordance of the trait for monozygotic and dizygotic twins and for adopted sibs, reared together and apart, is compared. These types of studies have shown that familial aggregation is stronger for male than for female homosexuality. Based on the threshold method for multifactorial traits, and varying the frequency of homosexuality in the population between 4 and 10%, heritability estimates between 0.27 and 0.76 have been obtained. In 1993, linkage between homosexuality and chromosomal region Xq28 based on molecular approaches was reported. Nevertheless, this was not confirmed in later studies. Recently, a wide search of the genome has given significant or close to significant linkage values with regions 7q36, 8p12 and 10q26, which need to be studied more closely. Deviation in the proportion of X chromosome inactivation in mothers of homosexuals seems to favor the presence of genes related with sexual orientation in this chromosome. There is still much to be known about the genetics of human homosexuality.
PMID: 19961060 [PubMed - indexed for MEDLINE]

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[Mare Tranquillity]

Rev Med Chil. 2008 Dec;136(12):1552-8. Epub 2009 Mar 23.
[Prenatal maternal mnemonic effects on the human neuro-psychic sex: a new proposition from fetus-maternal tolerance-rejection]
[Article in Spanish]
Valenzuela CY.
Programa de Genética Humana, Universidad de Chile, Chile. cvalenzu@med.uchile.cl
In approximately 15% of homosexual men, their phenotype is associated to the fraternal birth order. Older biological brothers induce in their mothers anti-male factors (antibodies) that interfere the brain maleness development of younger fetuses. This effect is seldom seen in non-right-handed men and is not seen in women. The influence of older siblings is seen in their sex ratio (SR). In contradiction with previous hypothesis, significant heterogeneities of SR have been found among older siblings of males or females, right or non-right-handed and homo or heterosexual individuals. This can only be understood as if the findings among homosexuals were part of a general mechanism of fetus-maternal tolerance-rejection processes of placental mammals. We found, in relation to ABO and Rh systems and sex, that embryos with genes different from those of their mothers, induced better pregnancies and maternal tolerance than embryos similar to their mothers. Assuming that homo or heterosexuality and right or non-right-handedness behave similar to ABO or Rh alleles, the author provides a speculative interpretation of these results. Homosexual women and especially if they are non-right-handed, are preceded by siblings with a high SR (maternal environment with anti-female or pro-male factors); then lesbianism or non-right-handedness may induce tolerance to be a woman in such anti-female environment. Non-right-handedness could induce tolerance for anti-male factors of mothers, thus preventing the production of gays in a pro-male maternal environment, but leading to the production of non-right-handed gays in anti-male maternal environments. Several new hypotheses and interpretations merge from this new proposition. Also, complete sexual orientation could be acquired after birth.
PMID: 19350172 [PubMed - indexed for MEDLINE]

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Behav Neurosci. 2009 Apr;123(2):252-6.
Hair whorl direction and sexual orientation in human males.
Rahman Q, Clarke K, Morera T.
Biological and Experimental Psychology Group, School of Biological Sciences, Queen Mary, University of London, United Kingdom. q.rahman@qmul.ac.uk
Hair whorl direction is a somatic feature that is organized early during neurodevelopment and unlikely to be influenced by social factors. This study aimed to replicate a widely reported association by A. J. S. Klar (2003) between counterclockwise hair whorl direction and homosexuality in men, using more objective methodology. The authors took digital photographs of parietal surface hair whorls from 100 heterosexual men and 100 homosexual men who were predominantly right-handed. These images were rated for clockwise and counterclockwise direction (for which no more than 1 hair whorl was present) by 2 raters unaware of sexual orientation. The authors found no significant difference between heterosexual and homosexual men in hair whorl direction, but the authors did replicate the fraternal birth order effect (more older brothers for homosexual men). Number of older sisters was positively correlated with counterclockwise hair whorls in heterosexual men. These data were discussed in relation to prenatal factors assumed to play a role in the neurodevelopment of male homosexuality. (c) 2009 APA, all rights reserved.
PMID: 19331448 [PubMed - indexed for MEDLINE]
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PLoS Genet. 2008 Dec;4(12):e1000313. Epub 2008 Dec 19.
Sexually antagonistic "zygotic drive" of the sex chromosomes.
Rice WR, Gavrilets S, Friberg U.
Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA, USA. rice@lifesci.ucsb.edu
Genomic conflict is perplexing because it causes the fitness of a species to decline rather than improve. Many diverse forms of genomic conflict have been identified, but this extant tally may be incomplete. Here, we show that the unusual characteristics of the sex chromosomes can, in principle, lead to a previously unappreciated form of sexual genomic conflict. The phenomenon occurs because there is selection in the heterogametic sex for sex-linked mutations that harm the sex of offspring that does not carry them, whenever there is competition among siblings. This harmful phenotype can be expressed as an antagonistic green-beard effect that is mediated by epigenetic parental effects, parental investment, and/or interactions among siblings. We call this form of genomic conflict sexually antagonistic "zygotic drive", because it is functionally equivalent to meiotic drive, except that it operates during the zygotic and postzygotic stages of the life cycle rather than the meiotic and gametic stages. A combination of mathematical modeling and a survey of empirical studies is used to show that sexually antagonistic zygotic drive is feasible, likely to be widespread in nature, and that it can promote a genetic "arms race" between the homo- and heteromorphic sex chromosomes. This new category of genomic conflict has the potential to strongly influence other fundamental evolutionary processes, such as speciation and the degeneration of the Y and W sex chromosomes. It also fosters a new genetic hypothesis for the evolution of enigmatic fitness-reducing traits like the high frequency of spontaneous abortion, sterility, and homosexuality observed in humans.
PMID: 19096519 [PubMed - indexed for MEDLINE]
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[Mare Tranquillity]

Orv Hetil. 2008 Aug 17;149(33):1555-60.
[Overview of the biological etiology of transsexualism]
[Article in Hungarian]
Kórász K, Simon L.
Semmelweis Egyetem, Altalános Orvostudományi Kar, Budapest, Hungary.
Gender identity disorder, or transsexualism as it is more commonly known, is a highly complex clinical entity. The general belief among behavioural scientists and physicians is that transsexualism is an identifiable and incapacitating disease which can be diagnosed and successfully treated by reassignment surgery. Although the exact etiology of gender identity disorder is unknown, several environmental, genetic and anatomical theories have been described. The reviewers draw attention to the possible genetic, hormonal, immunological and anatomical causes. An attempt is made to point out the future trends in research, highlighting their progressive features.
PMID: 18687574 [PubMed - indexed for MEDLINE]
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J Sex Med. 2009 Feb;6(2):449-55. Epub 2008 Jul 15.
Genetic factors increase fecundity in female maternal relatives of bisexual men as in homosexuals.
Ciani AC, Iemmola F, Blecher SR.
University of Padova, General Psychology, Padova, Italy. andrea.camperio@unipd.it
INTRODUCTION: Recent studies on male homosexuals showed increased fecundity of maternal female relatives of homosexual probands, compared to those of heterosexual controls. We have suggested that these data could be explained by the transmission, in the maternal line, of an X-linked genetic factor that promotes androphilic behavior in females and homosexuality in males. AIM: Our original studies were on relatives of male subjects who declared themselves to be exclusively homosexual. However, the relationship between homosexuality and bisexuality, including the possibility of shared genetic factors, is complex and largely unexplored. To cast light on this issue, in the present study we examined whether relatives of bisexuals show the same indirect fitness advantage as previously demonstrated for homosexuals. MAIN OUTCOME MEASURES: Subjects completed a questionnaire on their sexual orientation, sexual behavior, and their own and their relatives' fecundity. METHODS: We studied 239 male subjects, comprising 88 who were exclusively or almost exclusively heterosexual (pooled to comprise our "heterosexual" group), 86 who were bisexual, and 65 exclusively or almost exclusively homosexual individuals (pooled in our "homosexual" group). Bisexuals were here defined on the basis of self-identification, lifetime sexual behavior, marital status, and fecundity. RESULTS: We show that fecundity of female relatives of the maternal line does not differ between bisexuals and homosexuals. As in the previous study on homosexuals, mothers of bisexuals show significantly higher fecundity, as do females in the maternal line (cumulated fecundity of mothers, maternal grandparents, and maternal aunts), compared to the corresponding relatives of heterosexual controls.This study also shows that both bisexuals and homosexuals were more frequently second and third born. However, only homosexuals had an excess of older male siblings, compared to heterosexuals. CONCLUSIONS: We present evidence of an X-chromosomal genetic factor that is associated with bisexuality in men and promotes fecundity in female carriers.
PMID: 18637994 [PubMed - indexed for MEDLINE]

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PLoS One. 2008 Jun 18;3(6):e2282.
Sexually antagonistic selection in human male homosexuality.
Camperio Ciani A, Cermelli P, Zanzotto G.
Dipartimento di Psicologia Generale, Università di Padova, Padova, Italy. andrea.camperio@unipd.it
Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling 'Darwinian paradox'. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness), accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait.
PMID: 18560521 [PubMed - indexed for MEDLINE]
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Arch Sex Behav. 2008 Feb;37(1):85-99.
Sexual orientation in women with classical or non-classical congenital adrenal hyperplasia as a function of degree of prenatal androgen excess.
Meyer-Bahlburg HF, Dolezal C, Baker SW, New MI.
New York State Psychiatric Institute & Department of Psychiatry, Columbia University, 1051 Riverside Drive, New York, NY 10032, USA. meyerb@childpsych.columbia.edu
46,XX individuals with classical congenital adrenal hyperplasia (CAH) due to deficiency of the enzyme, 21-hydroxylase, show variable degrees of masculinization of body and behavior due to excess adrenal androgen production. Increased bisexuality and homosexuality have also been reported. This article provides a review of existing reports of the latter and presents a new study aimed at replicating the previous findings with detailed assessments of sexual orientation on relatively large samples, and at extending the investigation to the mildest form, non-classical (NC) CAH. Also, this is the first study to relate sexual orientation to the specific molecular genotypes of CAH. In the present study, 40 salt-wasters (SW), 21 SV (simple-virilizing), 82 NC, and 24 non-CAH control women (sisters and female cousins of CAH women) were blindly administered the Sexual Behavior Assessment Schedule (SEBAS-A, 1983 ed.; H. F. L. Meyer-Bahlburg & A. A. Ehrhardt, Privately printed). Most women were heterosexual, but the rates of bisexual and homosexual orientation were increased above controls not only in women with classical CAH, but also in NC women, and correlated with the degree of prenatal androgenization. Classifying women by molecular genotypes did not further increase the correlation. Diverse aspects of sexual orientation were highly intercorrelated, and principal components analysis yielded one general factor. Bisexual/homosexual orientation was (modestly) correlated with global measures of masculinization of non-sexual behavior and predicted independently by the degree of both prenatal androgenization and masculinization of childhood behavior. We conclude that the findings support a sexual-differentiation perspective involving prenatal androgens on the development of sexual orientation.
PMID: 18157628 [PubMed - indexed for MEDLINE]
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Arch Sex Behav. 2008 Feb;37(1):145-9.
Eye color, hair color, blood type, and the rhesus factor: exploring possible genetic links to sexual orientation.
Ellis L, Ficek C, Burke D, Das S.
Department of Sociology, Minot State University, Minot, ND 58707, USA. lee.ellis@minotstateu.edu
The present study sought to expand the limited evidence that sexual orientation is influenced by genetic factors. This was accomplished by seeking statistical differences between heterosexuals and homosexuals for four traits that are known to be genetically determined: eye color, natural hair color, blood type, and the Rhesus factor. Using a sample of over 7,000 U.S. and Canadian college students supplemented with additional homosexual subjects obtained through internet contacts, we found no significant differences between heterosexuals and homosexuals regarding eye color or hair color. In the case of blood type and the Rh factor, however, interesting patterns emerged. Heterosexual males and females exhibited statistically identical frequencies of the A blood type, while gay men exhibited a relatively low incidence and lesbians had a relatively high incidence (p < .05). In the case of the Rh factor, unusually high proportions of homosexuals of both sexes were Rh- when compared to heterosexuals (p < .06). The findings suggest that a connection may exist between sexual orientation and genes both on chromosome 9 (where blood type is determined) and on chromosome 1 (where the Rh factor is regulated).
PMID: 18074215 [PubMed - indexed for MEDLINE]

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[Mare Tranquillity]

How many pages of references do you want, DOT? In the absence of chemical pollutants it's primarily genetics, complex genetics and complex behaviors, just like in the animal world.

There is no reason for religious people to single out homosexual people for special discrimination or persecution--except for personal opprobrium.

 

[Mare Tranquillity]

Mostly for Siho, but of interest to DOT as well since it adds credence to my other posts and references.

MALE TO FEMALE TRANSSEXUAL INDIVIDUALS HAVE FEMALE NEURON
NUMBERS IN THE CENTRAL SUBDIVISION OF THE BED NUCLEUS OF THE STRIA
TERMINALIS
Dr Frank Kruijver, Dr Jiang-Ning Zhou, Dr Chris Pool, Dr Michel Hofman, Professor Louis
Gooren & Professor Dick Swaab
Published in the Journal of Clinical Endocrinology & Metabolism, Vol 85. No: 5, 2034-2041 (2000)
SYNOPSIS
This study followed one similar piece of research on much of the same brain material, and was thus
only the second of its kind to be done on human brains. The research team focussed on a part of the
brain understood to be sexually dimorphic, the central subdivision of the bed-nucleus of the stria
terminalis [BSTc]. The main neuron population of the BSTc is somatostatin-expressing [SOM]
neurons.* The team sought to determine the number of SOM neurons in the BSTc [only those
with visible nucleolus were counted], in relation to sex, sexual orientation, gender identity and past
or present hormonal status.
42 human brains were collected in total: eight [8] gender dysphoric individuals, six [6] of whom
were male-to-female individuals ( MtF, transwomen) and had undergone transition, including
hormone treatment and surgery, one [1] male-to-female individual who had undergone no treatment
whatever, but who had always strongly identified as female, and one [1] female-to-male individual
(FtM, transman).
The control group of 34 individuals included: nine [9] homosexual men, nine [9] heterosexual men,
ten [10] presumed heterosexual women, three [3] women with hormone disorders, three [3] men
with hormone disorders.
The findings indicated that, regardless of sexual orientation, men had almost twice as many SOM
neurons as women (P< 0.006). The number of SOM neurons in the BSTc of the transwomen [MtF]
was similar to the other women (P= 0.83). In contrast, the neuron number of a transman [FtM] was
found to be in the male range. Hormone treatment or sex hormone level variations in adulthood
seemed to have no impact on BSTc neuron numbers. The relative volumes of the BSTc were also
measured. All of the men, regardless of sexual orientation, had volumes which were similar; the
women and the transwomen [MtF] had similar volumes; the transman [FtM] fell into the same
range as the other men. The volumes of all men versus all women and transwomen [MtF] were
statistically highly significant (P< 0.01)
No statistical differences were found for age, post-mortem time, fixation time, storage time or cause
of death, nor were any differences found between early, rather than late, recognition of gender
dysphoria/transsexualism. The effects of variations in levels of estrogen, testosterone, antiandrogen
treatments and orchidectomy were also tested and appeared to have no effect on the BSTc.
The finding of SOM neuronal sex differences in the BSTc and the sex reversal of these differences
in the brains of gender dysphoric individuals, clearly supports the paradigm that in these
individuals, the sex differentiation of the brain and the genitals may go in opposite directions. This
points to a neurobiological basis, established during early development, for the condition of gender
dysphoria.* somatostatin is a polypeptide hormone, produced in the brain (and also the pancreas), which appears to inhibit the secretion of other hormones.
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