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Scientists claim to have taken a step towards resurrecting the woolly mammoth from extinction after recreating a gene from the Ice Age giants in human cells.

Researchers compared the genomes of two woolly mammoths with those of Asian elephants - their closest living relatives - in an attempt to understand the differences between them.

The work, which was conducted by scientists at the University of Chicago, has helped to reveal how woolly mammoths adapted to survive in the cold expanses the Arctic circle.

Now geneticists claim the study could act as a guide to show how modern elephants could be 're-engineered' to survive in Siberia and even bring the resurrection of woolly mammoths closer.

The last of the woolly mammoths (shown in the reconstruction above) were isolated on an Arctic island for around 5,000 years, forcing them to inbreed as their population dwindled until disappearing 4,500 years ago

The research, which has been published on the open science site bioRxiv, found that woolly mammoths and Asian elephants have nearly 1.4 million DNA letters difference between their genomes.

These difference alter more than 1,600 genes, bringing about changes in skin and hair development, fat storage, metabolism and temperature sensation.

As part of the study, the researchers even went as far as to 'resurrect' a single mammoth gene known as TRPV3, which was involved in sensitivity to the cold.

Dr Vincent Lynch, a geneticist at the University of Chicago who led the work and his colleagues, said: 'We have identified genetic changes unique to woolly mammoths, some of which likely contributed to woolly mammoth-specific traits.

'Our results suggest that changes in circadian systems, insulin signaling and adipose development, skin development, and temperature sensation may have played important roles in the adaptation of woolly mammoths to life in the high artic.'

Dr Lynch and his colleagues inserted mammoth and elephant TRPV3 gene into human cells in the lab and exposed them to different temperatures.

This shoed the mammoth TRPV3 gene is less responsive to heat than the elephant gene.

Dr Lynch told Nature that the next step was to insert the same gene into elephant cells that have been programmed to behave like embryonic cells.

This could begin the process to gradually altering elephant cells to become more and more like those of a woolly mammoth.

Professor George Church, a geneticist at Harvard Medical School in Boston, has already done similar work engineering elephant cells to contain 14 genes involved in cold tolerance.

He told Nature that this is a preamble to editing an entire woolly mammoth genome that could eventually lead to the animals being resurrected.

Alternatively Asian elephants could be altered with mammoth genes so that they could survive in Siberia.

"These are genes we would need to alter in an elephant genome to create an animal that was mostly an elephant, but actually able to survive somewhere cold," says Beth Shapiro, an evolutionary geneticist at the University of California, Santa Cruz.

Scientists have been able to extract DNA from mammoth hair (above) and tusks found across Siberia

Researchers extracted DNA from the remains of two woolly mammoths 20,000 and 60,000 years ago

A 16 square kilometre reserve in north Siberia, known as Pleistocene Park, has even been proposed as a home for such creatures.

However, many scientists are nervous of breeding 'woolly elephants' or brining mammoths back to life – particularly as the habitats they once thrived in are now under threat.

A recent study showed that for 5,000 years woolly mammoths clung on in just a tiny corner of the Arctic circle for around until they died out 4,500 years ago.

The population suffered severe inbreeding and may have struggled to find food in the changing climate.

HOW TO BRING BACK A MAMMOTH 

Scientists claim to have taken a major step towards recreating the woolly mammoth by inserting more than a dozen of the creature's genes into the live DNA of an elephant.

Researchers studied the structure of DNA from mammoths preserved in the Arctic to reproduce exact copies of 14 of the extinct animal's genes.

These were then integrated by experts at Harvard University in Massachusetts into the elephant genome - and functioned as normal DNA.

A new method known as 'Crispr' - helping scientists make accurate changes to DNA - was used by genetics professor George Church, who replaced parts of elephant DNA with the mammoth genes 

Other researchers have proposed using mammoth DNA to replace that of an elephant using a similar technique to the one used to clone Dolly the Sheep.

However, many scientists fear these animals would be unable to survive in the modern world without their ancient habitat.

Such techniques also can lead to deformities and health problems in the animals. 

Hendrik Poinar discusses whether we should bring back the mammoth