Researcher shows eggs are eggs

A Harvard Medical School researcher's claim that women might someday be able to generate new eggs appears to have been exploded.

The work was done by another Boston scientist, the Boston Globe reported.

Jonathan Tilly's report that mice appear to have germ cells that can generate new eggs raised hopes that women's reproductive years could be extended with injections of stem cells. He had apparently disproved the theory that women are born with all the eggs they will ever have.

Amy Wagers, a scientist at the Joslin Diabetes Center, used a tool known as "parabiotic mice" to demonstrate that Tilly's work had problems. Those are mice genetically engineered so one has cells that glow green, and joined with another mouse without the engineering so the two share one circulatory system.

If Tilly's theory was right, each mouse would eventually have some eggs that had originally been germ cells in the other mouse and had been circulating in its blood. But that never happened, the Globe reported.

Copyright 2006 by United Press International