Genetic Switch for Determining Gender Identified; Gene Linked to So-Called 'Intersex' Families

[Elmore Furth]

So it isn't just a Y chromosome that determines male gender. It's is more complicated than that.

The Y chromosome is supposed to genetically seal a fetus's fate in terms of gender. Males have one X and one Y chromosome, while females have two X chromosomes. Yet, in some families a child is born with an X and Y chromosome and develops physically as a female, although she may not menstruate, and her brothers and male cousins may have underdeveloped or ambiguous genitalia.

The newly identified gene, called MAP3K1, is not the first to be associated with sex determination. The so-called male gene called SRY was discovered on the Y chromosome 20 years ago, and since then a number of other such genes have been found. "But MAP3K1 may hold the key to understanding how these various genes are connected," says Dr. Ostrer.

Dr. Ostrer and collaborators in England, Australia, and France, spent nine years searching for the gene responsible for disorders of sex determination in two families, one in France and the other in New Zealand, and in several affected individuals. Different mutations in MAP3K1 were found in unrelated individuals. Some of the women in the study with the Y chromosome had only partially developed ovaries, an overdeveloped clitoris, and excessive hair, while others had tumors in their ovaries. Some of the men had a urethral opening on the underside of their penis or had an abnormally small penis. Some were also infertile. All of these individuals had a normal SRY gene, leading the researchers to suspect that MAP3K1 may influence the activity of that gene. Additional experiments in the study provide evidence for how that might be happening.

Approximately 1 in 1000 individuals is affected by these disorders, says Dr. Ostrer. To better understand the prevalence and identify new genes and pathways, he is setting up a national consortium to sequence the genomes of affected individuals and their parents.


Genetic Switch for Determining Gender Identified; Gene Linked to So-Called 'Intersex' Families

[provis99]

1. weird; I was just thinking about this topic today.

I was thinking about the rumors that Jamie Lee Curtis was an XY female.

[Poll_Blind]

2. BTW, you ever see this article:

I'm so happy I can't see straight interview with Tony Curtis?

She wanted to be a bigger star than him? “Yes, perhaps that was it. Jamie’s having a tough time now. She can’t play the ingénue any more, and that must be tough for her. A man can segue, but not a woman. It’s a very tough profession for a woman. So all of these things spark and come into it, you know. And there’s a secret in Jamie that I can’t disclose.”

He does, of course, off the record, necessitating an emergency breakfast the next day between me and his lawyer. The secret is really no one’s business.

Anyway, regardless she's one of the only skinny women I think is hot and her work with Dove (I think) where she didn't use any makeup- I thought that was just incredible. Women and girls have so many assaults on their self image, I thought Jamie Lee Curtis is one of the few people trying to make a difference on that front.

PB