[Controversial] The Scientific Evidence Regarding HBS
The HBS movement cites recent research on the hypothalamus as definitive "proof" of their assertion that transexuality is a physical intersex condition. Divorcing myself from the issue and speaking purely as a scientist, this is either ignorant or dishonest because the papers they cite are in fact only preliminary pilot studies.
The 1997 study by Zhou, Hofman, Gooren, and Swaab ("A Sex Difference in the Human Brain and its Relation to Transsexuality") was based on a sample group of six male-to-female transexuals, normalized against a control group of presumed heterosexual males, homosexual males, and presumed heterosexual females.
The 2001 follow-up study by Kruijver, Zhou, Pool, Hovman, Gooren, and Swaab ("Male-to-Female Transsexuals Have Female Neuron Numbers in a Limbic Nucleus") was based on the same sample group of six male-to-female transexuals plus one female-to-male transexual, normalized against a control group of 9 presumed heterosexual males, 9 homosexual males, and 10 presumed heterosexual females (26 of the controls were stated have been the same as the previous study).
The 2006 German study ("An Examination of the use of fMRT for diagnosing Transexuality") was based on twelve male-to-female transexuals, normalized against a control group of twelve heterosexual males and twelve heterosexual females.
I don't often "pull rank", but scientific research is something I can speak with considerable authority on as a former Caltech student -- and it's crystal clear that although the studies are legitimate, the conclusions the HBS advocates are trying to draw from them are completely unjustified. Arguing that the treatment of all transexuals should be radically redefined on the basis of this is absurdly premature, and further arguing that the only reason doctors don't toe the HBS line is that they are "are too busy to keep up with the most recent research about the brain and its relationship to gender" is frankly ludicrous.
In other words, the scientific evidence at this point is completely inconclusive, and anyone who claims otherwise is unequivocally wrong.
The 1997 study by Zhou, Hofman, Gooren, and Swaab ("A Sex Difference in the Human Brain and its Relation to Transsexuality") was based on a sample group of six male-to-female transexuals, normalized against a control group of presumed heterosexual males, homosexual males, and presumed heterosexual females.
The 2001 follow-up study by Kruijver, Zhou, Pool, Hovman, Gooren, and Swaab ("Male-to-Female Transsexuals Have Female Neuron Numbers in a Limbic Nucleus") was based on the same sample group of six male-to-female transexuals plus one female-to-male transexual, normalized against a control group of 9 presumed heterosexual males, 9 homosexual males, and 10 presumed heterosexual females (26 of the controls were stated have been the same as the previous study).
The 2006 German study ("An Examination of the use of fMRT for diagnosing Transexuality") was based on twelve male-to-female transexuals, normalized against a control group of twelve heterosexual males and twelve heterosexual females.
I don't often "pull rank", but scientific research is something I can speak with considerable authority on as a former Caltech student -- and it's crystal clear that although the studies are legitimate, the conclusions the HBS advocates are trying to draw from them are completely unjustified. Arguing that the treatment of all transexuals should be radically redefined on the basis of this is absurdly premature, and further arguing that the only reason doctors don't toe the HBS line is that they are "are too busy to keep up with the most recent research about the brain and its relationship to gender" is frankly ludicrous.
In other words, the scientific evidence at this point is completely inconclusive, and anyone who claims otherwise is unequivocally wrong.