Zoo to resurrect endangered species

New Scientist : Reminiscent of Michael Crichton’s 1990 novel Jurassic Park, the San Diego Zoo and the Scripps Research Institute in La Jolla, California, are collaborating to try to use frozen cells from dead animals to bring endangered species back from the brink of extinction. The team members have created induced pluripotent stem cells from frozen skin cells, which they hope to coax into becoming sperm and eggs. The San Diego Zoo currently has cell samples from more than 800 species. On a related note, Nature has called into question human stem-cell work done by researchers at the University of Tübingen. Thomas Skutella and coworkers had reported using cells from adult human testes to create pluripotent stem cells with similar properties to embryonic stem cells, whose use could avoid the ethical complications that arise concerning human embryonic tissue. However, some scientists questioned the evidence for pluripotency after reviewing the published paper and complained that Skutella would not distribute cells for verification.