SHANGHAI--Geneticist Xiaohui Wu looks through a window into a clean room on the campus of Fudan University here and proudly points to a growing collection of mutant mice. To a visitor, the 4000 cages and 20,000 mice representing 400 mutant strains look pretty impressive. To Wu, the scale of the operation is a frustrating limitation.

"We plan to mutate 70% of the mouse genome over the next 5 years," he says. Yet, their current facilities are filled to capacity. A new building will provide space for 10,000 more cages. But Wu needs 50,000 more, enough for about 100,000 mutant mice. Those cages, he says, require a lot more space and "a lot of money."

How fruit fly geneticist Tian Xu is transforming the mouse into a genetics workhorse to reveal the causes of human disease.

By Pat McCaffrey

Sitting in a standard-issue clear plastic cage among hundreds of other white laboratory mice, the piggyBac mouse looks absolutely ordinary, not a bit like an animal poised to turn human genetics research on its head. But when Tian Xu, Ph.D., professor of genetics, switches on an ultraviolet lamp, the mouse emits a faint pink glow—an aura that holds the secret of its transformative power. If Xu, professor and vice chair of genetics and the mouse’s inventor, has his way, he will breed up to a million more pink animals. Those animals, he says, will reveal the causes—and in some cases the cures—for myriad human diseases.