Mammoths: Scientists have deciphered the genome

Using a fragment of fossil DNA, scientists have discovered the genome of a 52,000-year-old woolly mammoths. It was found in Siberia. Now there is a chance to revive the extinct giant beasts.

A study was recently conducted that reconstructed the three-dimensional structure of the woolly mammoth chromosomes. The structure in the cell nucleus where DNA and proteins are organized into genes.

These genome samples were found in fossils. They consist only of tiny, jumbled fragments of DNA.

But the genome of a 52,000-year-old fossil mammoth can be reconstructed. This is because the animal was freeze-dried shortly after death. Its DNA was preserved in a glassy state.

It took five years to reconstruct the mammoth genome. And now, at last, the attempts have settled on an unusually well-preserved specimen of a fossil mammoth. It was found in northeastern Siberia in 2018.

According to scientists, this fossil has preserved much of the physical integrity of the chromosome, including proteins. These are the ones that contact genes.
Now scientists will be able to better understand the organization of the mammoth genome in its cells. This will also help to find out which genes were active at different periods of the animal’s life.

“This is a new type of fossil, and its scale dwarfs the scale of individual ancient fragments of DNA — a million times larger than the sequence,” said study co-author Erez Lieberman Eiden of Baylor College of Medicine.

What has already been learned about mammoths?

Researchers have created an ordered map of the mammoth genome. They used the genomes of modern elephants as a template. The results showed that woolly mammoths had 28 chromosomes. That’s how many modern Asian and African elephants have. Scientists could decipher the genes, through which they learned how the giant mammal got its woolliness and resistance to cold.

“For the first time, we have a woolly mammoth tissue for which we know roughly which genes were switched on and which genes were off,” said Marc A. Marty-Renom, another author of the study.

“This is an extraordinary new type of data, and it’s the first measure of cell-specific gene activity of the genes in any ancient DNA sample,” said Dr. Marty-Renom.

Woolly mammoths roamed the Earth’s northern hemisphere for more than half a million years. They began to disappear as a result of the last ice age about 10,000 years ago.

It wasn’t just climate change that drove them to extinction. Scientists suspect that heavy hunting by ancient humans led to their disappearance about 4,000 years ago. There’s a chance that this technique could be used to analyze other ancient DNA samples, such as Egyptian mummies, to reveal what they looked like and how they lived.

Source: https://uk.news.yahoo.com/woolly-mammoth-dna-uncovered-siberia-043210680.html?guccounter=1