Gene identified as crucial for female sexual development.(Gynecology)

The discovery of a single-gene mutation in an 18-year-old female patient who lacks a uterus and vagina suggests that, as with the male, much of female sexual development is directed by a single gene, reported Dr. Anna Biason-Lauber and colleagues.

The notion held by experts up until now was that male development was determined by sex-specific genes, while the female was the basic human gender.

The patient initially was seen for primary amenorrhea, said Dr. Biason-Lauber of University Children's Hospital, Zurich, Switzerland. On physical examination, she had a normal weight, mature breast and body-hair development, and a normal-sized clitoris. But her vaginal introitus was small and short, and she had acne that was being treated with antiandrogen therapy (N. Engl. J. Med. 351[8]:792-98, 2004).

Endocrine studies showed that she had increased androgen production, and magnetic resonance imaging revealed that she was missing a vagina and uterus, and that her right kidney was aplastic. She had normal-sized but ectopic ovaries.

The phenotype was consistent with Mayer-Rokitansky-Kuster-Hauser syndrome, which occurs with an estimated frequency of 1 in 5,000 females and is the second most common cause of primary amenorrhea after gonadal dysgenesis.

Previous studies with mice had shown that inactivating a single gene, ...