Homosexual Discussion Forum10% MythThank you, now I will do my own little bit of research and show where these studies have been shown in error.
BTW, LeVay's theories have been discounted by his peers, Chandler is not a scientist (I have Chandler's "A Second Creation", which is nothing more than his opinions backed up by lab techs not molecular geneticists), Hamer's book is misquoted (I have "The Science of Desire"), and your appeal to the APA's opinions are meaningless.
The Baily study is not an empirical study it is an anecdotal study by a human geneticist. So while I do my own research read this from another message board: Ladyberg wrote:In the summer of 1991 neurobiologist Simon LeVay introduced the world to the possibility of homosexuality being biological. LeVay claimed to have found a difference in the hypothalamus part of the brain structure between gay and straight men. The hypothalamus is a small area of the brain that is near the pituitary gland which is located at the base of the brain (see figure 1) (1). LeVay took brain tissue from forty-one routine autopsies. Nineteen of the 41 samples came from homosexual men who died from complications from AIDS (one bisexual was included in this category), and sixteen come from presumed heterosexual men (six of them died from AIDS and the rest form other causes). The last six came from presumed heterosexual women (only one woman died from AIDS, the rest from other causes) (6). LeVay’s research focused primarily on the third interstitial nucleus of the interior hypothalamus. This region is very small, making up only approximately .000009 percent of the brain's mass, and is known as INAH 3 (9). The INAH 3 is spherical or ellipsoidal in shape and is located about 1 mm lateral to the wall of the third ventricle (6) (see figure 2) (12). In his research he found that on average the size of the INAH 3 region in heterosexual males was about two to three times greater in volume than that of homosexual men and in women. With this LeVay concluded that this could be ultimately responsible for homosexual orientation (9).
Levay started his research by first fixing the brains by immersion for one to two weeks in 10 or 20% buffered formalin. Afterwards, the brains were sliced by hand at the thickness of about 1 cm in or close to the coronal plane (6). The coronal sections are any sections that divide the body into anterior and posterior sections and are perpendicular to the sagittal plane which runs side to side (see figures 3 and 4) (7, 12). Tissue blocks containing the anterior hypothalamus were then dissected from the slices made earlier and then stored for one to eight weeks in 10% buffered formalin. At this point the blocks were given code numbers in order to perform blind research, making it unknown to which group each sample came from, preventing any bias. The blocks were then infiltrated with 30% sucrose and then frozen-sectioned at a thickness of 52 micrometers in planes that were parallel to the original slices (6). Frozen-sectioning is when a sample is frozen and then tissue layers are shaved off for view under a microscope (see freeze-fracture pg. 140 in Biology text by Campbell for an example of this procedure) (2). After the blocks were frozen-sectioned, the sections were mounted serially on slides, dried, and then defatted in xylene. The samples were then stained with 1% thionin in acetate buffer for 15-20 minutes and then differentiated with 5% rosin in 95% alcohol for 4-10 minutes. After all of the slides were finally prepped, LeVay used a compound microscope with a camera lucida attachment at a linear magnification of x83 to trace the outlines of the four nuclei (the INAH 1, 2, 3, and 4) (6).
With the use of one-way analysis of variance (ANOVA) LeVay found that there were no differences found in the INAH 1, 2, or 4. He did find, however, that the INAH 2 was about two times larger in men than in women. But when the INAH 2 of the women were compared to that of men of similar ages, no sexual difference was found. With this LeVay concluded that the INAH 2 was not sexually dimorphic. LeVay did find that the INAH 3 to be dimorphic. He found that the volume of the nucleus was more than twice as large in the heterosexual men (0.12 ± 0.01 mm3, mean ± SEM) as in the homosexual men (0.051 ± 0.01 mm3). LeVay also noticed that the volume of the INAH 3 in homosexual men was similar to that of heterosexual women, which was 0.056 ± 0.002 mm3 (6).
There were many things that were questionable in LeVay’s research that in turn makes his results unreliable. The first problem was in his sample groups. Of the sixteen heterosexual men that were tested, only two of them, which were the ones that died of AIDS, denied any homosexual activity. For the other fourteen men there was no record available about their sexuality and they were assumed to be “mostly or all heterosexual on the basis of the numerical preponderance of heterosexual men in the population” (6). Not only is the actual sexuality of the sixteen assumed heterosexuals questionable, but so is the classification of the homosexuals in his sample groups. In determining degrees of sexual preference, the seven-point Kinsey scale is often used. When LeVay made his classification of the group of homosexuals he included all men that have had sexual encounters with men and he did not take into account any possible encounters they might have had with women. This is evident in how he included a bisexual in the group of homosexuals. This classification implies that there is a unity of sexual behavior between bisexual men and men who only have sex with men that simply does not exist (3). Another questionable item in LeVay’s research is in the measuring of the INAH. Considering the fact that the borders of the nucleus are not very clear, many scientists disagree on exactly how to measure INAH nuclei. The thing that makes the nucleus hard to measure is that it is seen as a scattering of cells, as seen in figure 5(1). Many feel that it is more accurate to count the actual numbers of the cells of the INAH 3, instead of just measuring the volume, like LeVay did. One way that this would help out is that it would rule out any measuring errors due to any possible swelling or shrinking of the nucleus caused by chemicals or by diseases (8).
The second major research that was performed to try to link genetics with homosexuality was the work of molecular biologist Dean Hamer and his research team. In the summer of 1993, Hamer announced that they discovered a link between the chromosome region Xq28 and male homosexuality. Hamer and his research team conducted interviews and took blood test from forty pairs of brothers, all of which were homosexual. The purpose was to see if they shared similarities in a particular segment of the q arm of the X chromosome, Xq28 (10) (see figure 6 for image of Xq28) (13). Hamer’s research started out with the recruitment of test subjects from various outpatient HIV clinics and from local homophile organizations. Through his recruitment he had 114 gay men for primary volunteers, 76 in which their family histories were not known and 38 that were known to have a gay brother (the 38 pairs of brothers came from Hamer’s sib-pair pedigree study and 2 more were added to this group from the random sample) (4). 142 relatives of both groups were interviewed in which 99 of them were male relatives and 43 were female. The relatives of the homosexuals were used to draw the sexual orientation in the family trees (5). When the interviews were completed, Hamer noticed that there was a higher number of maternal homosexual relatives compared to paternal relatives. With these results and the knowledge that males receive their single X chromosome from their mothers Hamer concluded that the gene was passed by the mother (4).
After Hamer finished establishing the sexual orientation in the subjects’ family trees, he began to try to find any X chromosomal linkage within the group of the homosexual brothers. At this point, blood samples were taken from the group of the 40 brothers, as well as from some of their relatives. All of the subjects were typed for a series of 22 markers that span along the X chromosome. From there they were categorized into three different groups according to those findings. If the mother was unavailable for testing and both of the brothers shared the same allele with one another, they were labeled as concordant-by-state. The brothers whose mothers were known to be heterozygous and shared the same allele were labeled as concordant-by-descent. The rest of the brothers that did not share the same allele were labeled as discordant and noninformative if the mother was known to be homozygous for the marker. The results of this research was that 33 of the 40 pairs of brothers shared the same allele in the area of Xq28. Hamer concluded from this that this find suggested that there is a locus, or maybe loci, that is related to sexual orientation in men lies within 4 million base pairs of DNA that are on the tip of the long arm of the X chromosome (4).
How reliable is Hamer’s research? One problem with his research is how he did not use heterosexual men as a control in his research. If heterosexual brothers shared the same markers, then the whole idea of this particular marker being connected to homosexuality is completely nullified. Another issue with his research is that he only tested the possible alleles of 15 of the 40 mothers. This means that it was unknown as to if the untested moms were homozygous or not. The rest of the mothers were classified as homozygous for the marker by using the population frequency of the allele coinherited by the brothers (4). This in itself leaves plenty of room for error in the results. There have been other researchers who have tried to duplicate Hamer’s research with no luck. In April of 1999 George Rice and his team tried to duplicate Hamer’s findings by using 52 gay brothers in their research. They examined the same markers and their results did not match the results of Hamer. They concluded that their results did not support any X-linked gene for homosexuality (11).
In short, science has not been able to truly form a biological link to homosexuality. Aside from all of the problems with the research procedures of LeVay and Hamer, the research in itself forces one to rely on assumptions to take in the results as fact. Also, all of the attempts that have arose to try to prove homosexuality as being biological comes from a naturalist point of view. According to naturalist thinking in this situation, if there is a biological link to homosexuality it would be considered immoral to discriminate against homosexuals. If there was indeed a link, discrimination against homosexuals would be no different than discriminating against someone because of their height, nose shape, color of their skin, etc. Unfortunately, it is naturalist philosophy that is serving as evidence as this point instead of true scientific fact.
Works Cited
1. Aamir, Munaff, et al. WhatCloset?!. http://homepage.mac.com/ihuggermugger/what...lity-brain.html
2. Campbell, Neil A., and Jane B. Reece. Biology. 6th ed. San Francisco: Benjamin Cummings, 2002. 140.
3. Carrier, Joseph M., and George Gellert. “Biology and Homosexuality”. Science 1 November 1991: 630
4. Hamer, Dean, et al. “A Linkage Between DNA Markers on the X Chromosome and Male Sexual Orientation.” Science 16 July 1993: 321-327.
5. Hamer, Dean, and Peter Copeland. The Science of Desire. New York, New York: Simon and Schuster,1994.
6. LeVay, Simon. “A Difference in Hypothalamic Structure between Heterosexual and Homosexual Men.” Science 30 August 1991: 1034-1037.
7. MadSci. Washington University Medical School. 15 May 2003 http://www.madsci.org/~lynn/VH/planes.html
8. Marshall, Eliot. “When Does Intellectual Passion Become Conflict of Interest”. Science New Series, Vol. 257, No. 5070. 31 July 1992. 620-625.
9. Nimmons, David. “Sex and the Brain.” Discover 15:3 (1994): 64-71.
10. Peters, Ted. Playing God? New York, New York: Routledge, 1997.
11. Rice, George, et al. “Male Homosexuality: Absence of Linkage to Microsatellite Markers at Xq28.” Science 23 April 1999.665-667.
12. The W.U.S.M. Neuroscience Tutorial. The Washington University School of Medicine. Copyright 1997 http://thalamus.wustl.edu/course/corhor.html
http://standing4christ.com/forum/postin ... =quote&p=6
13. YACs on Chromosome X. Unknown (Forbidden access to homepage). http://www.biologia.uniba.it/rmc/2-YAC-BAC/YAC/YAC-X.html
Animal research where scientists artificially change their chemical balance does not prove anything but that you can increase the aggressiveness of females by pumping them full of male hormones. When men are treated with female hormones (which was one APA sanctioned therapy for gays) all that happens is they develop breasts and treatment with testosterone (anabolic steroids) can cause cancer and other problems. I have two dogs that will hump anything that moves but that does not mean they are genetically gay, it means that they are no female dogs available for humping and the dogs have a biological need to hump.
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