Genital tubercle

Genital tubercle
Stages in the development of the external sexual organs in the male and female.
Details
Precursor	somatopleure
Gives rise to	genital swelling, mons pubis, clitoris, penis
Identifiers
Latin	tuberculum phallicum; tuberculum genitale
Code	TE E5.7.4.0.1.0.1
Anatomical terminology []

A genital tubercle or phallic tubercle is a body of tissue present in the development of the reproductive system. It forms in the ventral, caudal region of mammalian embryos of both sexes, and eventually develops into a primordial phallus. In the human fetus, the genital tubercle develops around week 4 of gestation, and by week 9 becomes recognizably either a clitoris or penis. This should not be confused with the sinus tubercle which is a proliferation of endoderm induced by paramesonephric ducts. Even after the phallus is developed, the term genital tubercle remains, but only as the terminal end of it, which develops into either the glans penis or the glans clitoridis.

The genital tubercle is sensitive to dihydrotestosterone and rich in 5-alpha-reductase, so that the amount of fetal testosterone present after the second month is a major determinant of phallus size at birth.