Genetic tug of war determines gender

May 23, 2006

U.S. scientists says whether a mammalian egg develops into a male or female is determined by a struggle between genes encoding signaling proteins.

The international study, led by Duke University Medical Center cell biologists, determined genes Wnt4 and Fgf9 are balanced during the early stages of development in the mammalian gonad before it commits to either a male testis or a female ovary. If that equilibrium is tipped in favor of Wnt4, the gonad develops into an ovary, while an Fgf9 victory leads to the formation of a testis.

What tips the balance in favor of male is a third gene, Sry, located on the Y chromosome in the genome and known to be the primary sex-determining gene in mammals, researchers said. When Sry becomes activated at a crucial moment during the early gonad's development, it favors Fgf9 and leads to testis development, said Blanche Capel, senior member of the international research team.

The study appears in the May 22 issue of the journal Public Library of Science-Biology.

Copyright 2006 by United Press International

Related Stories

Recommended for you

Moonlighting molecules: Finding new uses for old enzymes

November 27, 2015

A collaboration between the University of Cambridge and MedImmune, the global biologics research and development arm of AstraZeneca, has led researchers to identify a potentially significant new application for a well-known ...

Four pre-Inca tombs found in Peru's Lima

November 27, 2015

Archaeologists in Peru have found four tombs that are more than 1,000 years old in a pyramid-shaped cemetery that now sits in the middle of a residential neighborhood in Lima, experts said.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.