cut your finger off and see if it grows back.

Missing Limb? Salamander May Have Answer

By ANDREW POLLACK
Published: September 24, 2002
In a closetlike room at the ''Leg Lab'' here, salamanders stare blankly out of clear plastic drinking cups. The lab is so named because many of the animals have had, or will have, a leg cut off. But the salamanders recover, with perfect new limbs growing back in weeks.

Salamanders are the superstars of regeneration. They can grow back not only limbs but also tails, parts of their hearts and the retinas and lenses in their eyes. Humans cannot do any of that. So scientists here hope that the salamander's tricks may one day be applied to people.

''I really do believe it's just a matter of time before you're going to regenerate an arm or at least a finger,'' said Dr. David M. Gardiner, a biologist who runs the laboratory at the University of California at Irvine with Dr. Susan V. Bryant, the dean of biological sciences and his wife. ''I'd like to see that in my lifetime.''

Regenerative medicine, regrowing or repairing damaged organs, has become a hot topic. Almost all the attention has focused on stem cells. The idea is to grow stem cells outside the body, turn them into particular types of tissue and transplant them into patients.