Nola, the only surviving northern white rhinoceros at the San Diego Zoo Safari Park, rests at the facility on Dec. 18. / photo by Charlie Neuman * U-T San Diego

When the northern white rhinoceros Angalifu died at the San Diego Zoo Safari Park last week, he left his species a step closer to extinction. Only five of his kind remain, most of them elderly.

However, the gentle, two-ton animal also left behind a part of himself that may let scientists breathe new life into the imperiled species. They plan to use DNA samples preserved in the San Diego Frozen Zoo to create more white rhinos.

In their most ambitious vision something that has never been tried for any creature other than lab mice the researchers aim to coax skin cells from Angalifu and others of his kind to become stem cells, and then sperm and eggs, and then implant the embryos in surrogate rhinos.

This approach would go beyond cloning by producing more genetic diversity in the resulting offspring. Its unclear how long scientists will need to achieve the unprecedented feat, but they remain committed to the years-long effort.

Its really brilliant in retrospect that when animals die, you can freeze some of their cells and theyll last forever, said Jeanne Loring, a stem cell pioneer at The Scripps Research Institute in La Jolla who is a member of the project.

Angalifu came to the San Diego Zoo in 1990, joining two females, Nola and Noti, who had arrived a year earlier. The easygoing animals were favorites with zookeepers, who enjoyed training them and scratching their thick but sensitive hides.

Northern white rhinos, which once roamed central Africa in Chad, Uganda, Sudan and the Central African Republic, have been nearly wiped out by civil war and poaching. Their horns are valued as dagger handles and are mistakenly seen as an aphrodisiac or medicinal aid.

Researchers and zoo officials in several countries decided to try to preserve the species through captive breeding of the few remaining northern white rhinoceroses.

The San Diego Zoo Safari Park had succeeded in breeding southern white rhinos, a close relative of the northern variety. Nearly 100 southern white calves have been born at the facility.

The rest is here:
Can scientists clone a rhinoceros?