Bambi Eloriaga-Amago
In a remote village in the Dominican Republic, there is a group of people known as the Guevedoces. They are born looking like females, but as soon as puberty hits, they develop larger muscles, grow more hairy, and they begin to sprout testes and penises.
The Guevedoces, which literally means “penis at 12,” suffer from a medical condition called 5-alpha-reductase deficiency. It was first chronicled in the 1970s by Dr. Julianne Imperato, who was then working as an endocrinologist at Cornell University.
To understand this unique condition, we need to understand the processes that happen in the womb. In the first eight weeks of life, fetuses are neither male nor female. After the eighth week, the male hormone testosterone is sent to a structure called a tubercle. In a male fetus, the testosterone is converted into dihydro-testosterone, a hormone that turns the tubercle into a penis. However, females don’t produce dihydro-testosterone, so the tubercle instead becomes a clitoris.
Dr. Imperato found that the enzyme, 5-alpha reductase is the one that converts testosterone to dihydro-testosterone, and this is the enzyme that the Guevedoces lack. So the boys are born with what seems like female genitalia, but upon hitting puberty—when the body is again bombarded with testosterone—the male genitalia begin to sprout. This time, the body does respond to the surge in male hormones.
The resulting penis is a little under-sized, but it functions normally. The testes also produce sperm. So a Guevedoce can live his life normally after hitting puberty. The condition is inherently genetic, but it is still unclear why it is so prevalent in this particular region of the Dominican Republic.
