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

When words, structured data are placed on single canvas

October 22, 2017

If "ugh" is your favorite word to describe entering, amending and correcting data on the rows and columns on spreadsheets you are not alone. Coda, a new name in the document business, feels it's time for a change. This is ...

Mountain glaciers shrinking across the West

October 22, 2017

Until recently, glaciers in the United States have been measured in two ways: placing stakes in the snow, as federal scientists have done each year since 1957 at South Cascade Glacier in Washington state; or tracking glacier ...

Study finds pollution is deadlier than war, disaster, hunger

October 20, 2017

Environmental pollution—from filthy air to contaminated water—is killing more people every year than all war and violence in the world. More than smoking, hunger or natural disasters. More than AIDS, tuberculosis and ...

Dawn mission extended at Ceres

October 20, 2017

NASA has authorized a second extension of the Dawn mission at Ceres, the largest object in the asteroid belt between Mars and Jupiter. During this extension, the spacecraft will descend to lower altitudes than ever before ...

Metacognition training boosts gen chem exam scores

October 20, 2017

It's a lesson in scholastic humility: You waltz into an exam, confident that you've got a good enough grip on the class material to swing an 80 percent or so, maybe a 90 if some of the questions go your way.

0 comments

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.