NationStates Jolt Archive


Nature, nurture, and all that

Nadkor
27-10-2008, 04:09
Not about homosexuality, this time.

Australian researchers have identified a significant link between a gene involved in testosterone action and male 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.

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."

The BBC (http://news.bbc.co.uk/1/hi/health/7689007.stm)

What do you think? Does information like this change how you view transexuals? How do you feel about society's perception and treatment of transgendered and transexual individuals? Should new information like this change the "social stigma" that Prof Harley identifies? What way do you fall on the nature/nurture argument, particularly in regards to transexualism?
Smunkeeville
27-10-2008, 04:13
It doesn't really. I never had a problem with it. My nephew is finally being accepted by her mother, her father is still confused and mean. I see how painful it is for her, I wouldn't presume to tell her she is lying when she says she feels like a girl.
Lunatic Goofballs
27-10-2008, 04:18
I don't think it matters one whit whether it's biological, environmental or choice. If it's biological, it's no more right or wrong to discriminate against a transsexual as against a black man. If it's a lifestyle choice, it's no more right or wrong to discriminate against a transsexual as against a jew.

The benefit I suppose is in the science of genetics, but I question the need to study the genetics of gender and sexuality as if looking for an excuse or a justification. Personally, I'm looking at the potential for a new breed of party pranks. ;)