In lab rats, "Who's your daddy?" can now yield a surprising answer. Scientists have generated rats from mice that developed rat sperm.
The breakthrough marks the first time researchers produced healthy offspring from sperm cells fostered in a different species. The hope is this method could help generate sperm from endangered species or prize bulls.
A decade ago, scientists successfully developed sperm in one animal that had come from cells in another. Researchers began by growing rat sperm in mice, and proceeded to foster sperm from hamsters, rabbits, pigs, bulls and humans in mice as well....
More....