<p>Previous efforts in the 1990s to recover nuclei in cells from the skin and muscle tissue of mammoths found in Siberia failed because the region's extreme cold had damaged them.<br /><br />But a technique pioneered in 2008 by Teruhiko Wakayama of the Riken Centre for Developmental Biology, Japan, was successful in cloning a mouse from the cells of another mouse frozen for 16 years.<br /><br />Now that hurdle has been overcome, Akira Iritani, professor at Kyoto University, is re-activating his campaign to resurrect the woolly mammoth species that died out over 12,000 years ago.<br /><br />According to scientists, woolly mammoths became extinct about 10,000 BC when a comet exploded in the earth's atmosphere and caused fires.<br /><br />"Now the technical problems have been overcome, all we need is a good sample of soft tissue from a frozen mammoth," he told the Daily Telegraph.<br /><br />Iritani intends to use Wakayama's technique to identify the nuclei of viable mammoth cells before extracting the healthy ones.<br /><br />The nuclei will then be inserted into the egg cells of an African elephant, which will act as the surrogate mother for the mammoth.<br /><br />Iritani said he estimates that another two years will be needed before the elephant can be impregnated, followed by the approximately 600-day gestation period.<br /><br />He has announced plans to travel to Siberia in the summer to search for mammoths in the permafrost and to recover a sample of skin or tissue that can be as small as 3cm square.</p>
<p>Previous efforts in the 1990s to recover nuclei in cells from the skin and muscle tissue of mammoths found in Siberia failed because the region's extreme cold had damaged them.<br /><br />But a technique pioneered in 2008 by Teruhiko Wakayama of the Riken Centre for Developmental Biology, Japan, was successful in cloning a mouse from the cells of another mouse frozen for 16 years.<br /><br />Now that hurdle has been overcome, Akira Iritani, professor at Kyoto University, is re-activating his campaign to resurrect the woolly mammoth species that died out over 12,000 years ago.<br /><br />According to scientists, woolly mammoths became extinct about 10,000 BC when a comet exploded in the earth's atmosphere and caused fires.<br /><br />"Now the technical problems have been overcome, all we need is a good sample of soft tissue from a frozen mammoth," he told the Daily Telegraph.<br /><br />Iritani intends to use Wakayama's technique to identify the nuclei of viable mammoth cells before extracting the healthy ones.<br /><br />The nuclei will then be inserted into the egg cells of an African elephant, which will act as the surrogate mother for the mammoth.<br /><br />Iritani said he estimates that another two years will be needed before the elephant can be impregnated, followed by the approximately 600-day gestation period.<br /><br />He has announced plans to travel to Siberia in the summer to search for mammoths in the permafrost and to recover a sample of skin or tissue that can be as small as 3cm square.</p>