US researchers find evidence that homosexuality linked to genetics

The Guardian is reporting that scientist are drawing closer to proving a genetic link to sexuality. On the one hand this is encouraging, but on the other it's scary. Does this mean that parents will be able to request gene therapy to ensure they child doesn't turn out to be gay? Is that even ethical...

Compared to straight men, gay men are more likely to be left-handed, to be the younger siblings of older brothers, and to have hair that whorls in a counterclockwise direction.

US researchers are finding common biological traits among gay men, feeding a growing consensus that sexual orientation is an inborn combination of genetic and environmental factors that largely decide a person's sexual attractions before they are born.

Such findings - including a highly anticipated study this winter - would further inform the debate over whether homosexuality is innate or a choice, an undercurrent of California's recent Proposition 8 campaign in which television commercials warned that "schools would begin teaching second-graders that boys could marry boys", suggesting homosexuality would then spread.

Some scientists say the political and moral debate over same-sex marriage frequently strayed from established scientific evidence, including comments by Republican vice-presidential candidate Sarah Palin that homosexuality is "a choice" and "a decision".

Until 2007, CNN polls had found that a majority of Americans believed gay people could change their sexual orientation if they chose to; it was only last year that a majority for the first time said homosexuality was an inborn trait.

You can read more about these latest discoveries after the jump...

Transsexual gene link identified

For those that look to a science to explain phenomenon like male to female transsexuals, there argument has gotten stronger. The BBC is reporting a new break through in genetic science concerning out transgender brothers and sisters:

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.

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.

Find the rest of this article after the jump...