Androgen Insensitivity Syndrome
Women with the syndrome are genotypically male (XY) but phenotypically (look like) females. In the case of complete AIS he/she would have undescended testes and a blind-end vagina (no ovaries or uterus).
Typically these women tend to be tall and very attractive, with long limbs, immaculate skin, a thick head of hair, and little pubic hair. Often they don't realize they have the syndrome until puberty when secondary sex characteristics (breasts) develop without menstruation.
I ask because some science literature claims that a disproportionate number of women in the modeling industry have it, but I've never seen hard facts. Maybe it's just an outsider bias eager to validate the idea that high fashion models aren't "real" women.
ABC medical mysteries clip if you're interested: http://abcnews.go.com/video/playerIndex?id=5544655
This syndrome is not the same as hermaphrodites (e.g. what rumors say Jamie Lee Curtis is). Hermaphrodites have both male and female reproductive organs. People with AIS would only have testes.
Interesting thing is, if you google AIS Gemma Ward comes up a few times.
Gemma is speculated to have the opposite syndrome called trisomy x - which is basically the opposite of this, in that the female has 3 X chromosomes, so she's more female than most females. It basically says that the female has an extra X chromosome, making her a type of super-female. They may be very tall, and have very striking features. It's the same concept as down syndome, except a victim of down syndrome has an extra 21st chromosome.
Just look at the description of trisomy x:
(small head), round face, hypertelorism (wide-spread eyes), micrognathia (small chin), epicanthal folds (inner eye folds), low-set ears, hypotonia (poor muscle tone),
So any of you want to start the speculations? Which model might have AIS? (Anabela, THE model expert, I’m looking to you!)
And since you cannot have any babies without ovaries, this rules out Natalia Vodianova, or any fertile models with offspring.