| Themes > Science > Zoological Sciences > Endangered and Rare Species > Endangered Species > CLONING: Bringing Back Endangered Species > Endangered Sheep Survives Cloning |
Biotechnologists have announced the birth of the first surviving clone of an endangered mammal - a rare species of wild Mediterranean sheep called a European mouflon lamb. The six-month-old creature, which is being looked after at a wildlife centre in Sardinia, Italy, was cloned under the same technique used to create Dolly the sheep in 1997, they report in the October issue of Nature Biotechnology. The team was led by Pasqualino Loi of the University of Teramo, Italy, and included a scientist from the "Dolly" team, the Roslin Institute in Edinburgh. Process The so-called somatic cell nuclear transfer technique entails taking DNA from a donor cell and inserting it into a cultured egg whose nucleus has been removed. After the egg divides, the embryo is then implanted into a surrogate mother. The offspring is a copy, or a clone, of the animal which provided the donor DNA for insertion into the egg nucleus. The denucleated eggs for the mouflon lamb came from domestic, or farmyard sheep. Donor cells came from two female mouflons found dead in a pasture. Four embryos were transferred to four surrogate mothers, all of them domestic sheep. One of the transfers resulted in a successful pregnancy. "Our findings support the use of cloning for the expansion of critically endangered populations," the scientists say. "Ultimately, endangered wild animals could perhaps be salvaged or maintained using the oocytes [developing egg cells] and wombs of their unthreatened domesticated counterparts." The mouflon lamb is found on the islands of Sardinia, Corsica and Cyprus. Other clones Cattle, pigs and goats have followed the same path as Dolly, but efforts to clone endangered mammals had all met with failure. The first endangered animal to be cloned, a wild cow called a gaur, was born in the United States in January, but died within 48 hours. Environmentalists have mixed feelings about cloning endangered species, or setting up DNA banks with their preserved cells. A common view is that it is more important to save a species' habitat rather than to clone it, as there is no point releasing an animal into an environment where it has little chance of survival. The 2000 Red List of endangered species published by the World Conservation Union identifies 5,485 animal species as threatened, of which 180 are mammals. |
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