What we already knew getting some scientific collaboration
Just some news being passed along that makes things a bit clearer for the queerer...
http://news.bbc.co.uk/2/hi/health/7689007.stm
Transsexual gene link identified
Australian researchers have identified a significant link between a
gene involved in testosterone action and male-to-female
transsexualism.
DNA analysis from 112 male-to-female transsexual volunteers showed
they were more likely to have a longer version of the androgen
receptor gene.
The genetic difference may cause weaker testosterone signals, the
team reported in Biological Psychiatry.
However, other genes are also likely to play a part, they stressed.
Increasingly, biological factors are being implicated in gender
identity.
There is a social stigma that transsexualism is simply a lifestyle
choice, however our findings support a biological basis of how gender
identity develops
Professor Vincent Harley, researcher
One study has shown that certain brain structures in male-to-female
transsexual people are more "female like".
In the latest study, researchers looked for potential differences in
three genes known to be involved in sex development - coding for the
androgen receptor, the oestrogen receptor and an enzyme which
converts testosterone to oestrogen.
Comparison of the DNA from the male to female transsexual
participants with 258 controls showed a significant link with a long
version of the androgen receptor gene and transsexualism.
Testosterone
It is known that longer versions of the androgen receptor gene are
associated with less efficient testosterone signalling.
This reduced action of the male sex hormone may have an effect on
gender development in the womb, the researchers speculated.
"We think that these genetic differences might reduce testosterone
action and under masculinise the brain during foetal development, "
said researcher Lauren Hare from Prince Henry's Institute of Medical
Research.
Co-author Professor Vincent Harley added: "There is a social stigma
that transsexualism is simply a lifestyle choice, however our
findings support a biological basis of how gender identity develops."
Although this is the largest genetic study of transsexualism to date,
the researchers now plan to see if the results can be replicated in a
larger population.
Terry Reed from the Gender Identity Research and Education Society
said she was convinced of a biological basis to transsexualism.
"This study appears to reinforce earlier studies which have indicated
that, in some trans people, there may be a genetic trigger to the
development of an atypical gender identity.
"However, it may be just one of several routes and, although it seems
extremely likely that a biological element will always be present in
the aetiology of transsexualism, it's unlikely that developmental
pathways will be the same in all individuals. "
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/7689007.stm
Published: 2008/10/26 13:01:09 GMT
© BBC MMVIII
http://news.bbc.co.uk/2/hi/health/7689007.stm
Transsexual gene link identified
Australian researchers have identified a significant link between a
gene involved in testosterone action and male-to-female
transsexualism.
DNA analysis from 112 male-to-female transsexual volunteers showed
they were more likely to have a longer version of the androgen
receptor gene.
The genetic difference may cause weaker testosterone signals, the
team reported in Biological Psychiatry.
However, other genes are also likely to play a part, they stressed.
Increasingly, biological factors are being implicated in gender
identity.
There is a social stigma that transsexualism is simply a lifestyle
choice, however our findings support a biological basis of how gender
identity develops
Professor Vincent Harley, researcher
One study has shown that certain brain structures in male-to-female
transsexual people are more "female like".
In the latest study, researchers looked for potential differences in
three genes known to be involved in sex development - coding for the
androgen receptor, the oestrogen receptor and an enzyme which
converts testosterone to oestrogen.
Comparison of the DNA from the male to female transsexual
participants with 258 controls showed a significant link with a long
version of the androgen receptor gene and transsexualism.
Testosterone
It is known that longer versions of the androgen receptor gene are
associated with less efficient testosterone signalling.
This reduced action of the male sex hormone may have an effect on
gender development in the womb, the researchers speculated.
"We think that these genetic differences might reduce testosterone
action and under masculinise the brain during foetal development, "
said researcher Lauren Hare from Prince Henry's Institute of Medical
Research.
Co-author Professor Vincent Harley added: "There is a social stigma
that transsexualism is simply a lifestyle choice, however our
findings support a biological basis of how gender identity develops."
Although this is the largest genetic study of transsexualism to date,
the researchers now plan to see if the results can be replicated in a
larger population.
Terry Reed from the Gender Identity Research and Education Society
said she was convinced of a biological basis to transsexualism.
"This study appears to reinforce earlier studies which have indicated
that, in some trans people, there may be a genetic trigger to the
development of an atypical gender identity.
"However, it may be just one of several routes and, although it seems
extremely likely that a biological element will always be present in
the aetiology of transsexualism, it's unlikely that developmental
pathways will be the same in all individuals. "
Story from BBC NEWS:
http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/7689007.stm
Published: 2008/10/26 13:01:09 GMT
© BBC MMVIII