Brain May 'Hard-Wire' Sexuality Before Birth

[Az]

From http://www.sciencedaily.com/releases/2003/10/031022062408.htm

Excerpt
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Refuting 30 years of scientific theory that solely credits hormones for brain development, UCLA scientists have identified 54 genes that may explain the different organization of male and female brains. Published in the October edition of the journal Molecular Brain Research, the UCLA discovery suggests that sexual identity is hard-wired into the brain before birth and may offer physicians a tool for gender assignment of babies born with ambiguous genitalia.

“Our findings may help answer an important question — why do we feel male or female?” said Dr. Eric Vilain, assistant professor of human genetics and urology at the David Geffen School of Medicine at UCLA and a pediatrician at UCLA’s Mattel Children’s Hospital. “Sexual identity is rooted in every person’s biology before birth and springs from a variation in our individual genome.”

Since the 1970s, scientists have believed that estrogen and testosterone were wholly responsible for sexually organizing the brain. In other words, a fetal brain simply needed to produce more testosterone to become male. Recent evidence, however, indicates that hormones cannot explain everything about the sexual differences between male and female brains.

Vilain and his colleagues explored whether genetic influences could explain the variations between male and female brains. Using two genetic testing methods, they compared the production of genes in male and female brains in embryonic mice — long before the animals developed sex organs.

To their surprise, the researchers found 54 genes produced in different amounts in male and female mouse brains, prior to hormonal influence. Eighteen of the genes were produced at higher levels in the male brains; 36 were produced at higher levels in the female brains.

[demnan]

1. This would help explain

why people find they were "born into the wrong sex" and get sex change operations - they have the genes for one sex in the brain and the genitals of the other sex.

[webDude]

2. Man, talk about data that could be used for good as well as evil,...

imagine the possibilities. Well, at least you could explain it to your parents.

[mhr]

4. You Are Right, The Gay and Lesbian Community

Would see this as affirmation.

The radical right wingers would see this as affirmation as well to begin a pogrom to cleanse society of this menace.

I can hear the sermons now.

"God does not tolerate abominations even if they are genetic."

"Patrons, stand with we me now as we pray for deliverance from this evil and the speedy dispatch of all those afflicted."

"Never again shall devil genes walk the face of this earth."

[Brucey]

3. Hard-wired is a poor analogy.

Brains are dynamic, plastic. Even genes are dynamic. The old view that genes are static and unchanging is wrong. Nothing about us physically or psychologically is inherited. Recipes are inherited. Some of those recipes are more difficult to change than others, a concept called canalization. There are many ways to define gender. It is certain that genes contribute to gender identity. The finding of particular genes in mice will make it easier to locate similar genes in humans. However, I am worried about how this will be interpreted by the masses.

[TrogL]

5. genes change?

First I've heard of this.

Elucidate please.

[TahitiNut]

6. duplicate (and old news)

See http://www.democraticunderground.com/discuss/duboard.php?az=show_topic&forum=115&topic_id=1932

I'm locking this thread. Interested DUers are welcome to continue discussing this in the referenced thread.

Thank you for your understanding and cooperation,
TahitiNut - DU moderator