Biology: Resurrecting the woolly mammoth may be impossible
Withdraw a sufficient amount of genome of an extinct mouse may have set the tone for scientists resurrect extinct animals such as the woolly mammoth. This is extremely impossible and de-extinction is more complex than the researchers thought. The study in this regard shows how close the researchers are, but somewhat far from being able to bring extinct species back to life, transforming them genetically.
At the moment no species have yet been revived, but de-extinction is of interest to many futurist biologists. Part of the charm is simply the promise to see a missing species come to life. However also returning a key animal to its original habitat could help restore ecosystems. The woolly mammoth once kept arctic shrubs and trees in check and fertilized grasses with their manure. According to experts, there is much hope and hype that de-extinction will save us from ecosystem failure.
Woolly mammoth, resurrecting it seems impossible
To get this process started the genome of extinct species must first be sequenced, that is to modify the DNA of a relative of theirs that corresponds to it. Then comes the challenge of create embryos with the revised genome and carry them out in a living surrogate mother. Scientists have currently sequenced the genomes of more than 20 extinct species, but no one has yet claimed to have recreated the extinct genome of a living relative. The new study has started to think small: a Christmas Island rat, which disappeared in 1908 west of Australia.
This species is a perfect candidate for de-extinction, as it is a close relative of the Norwegian rat, a laboratory animal with a complete genome that scientists already know how to modify. They extracted DNA from the skins of two preserved Christmas Island rats and sequenced it many times to get as much genome as possible. The old DNA survives only in small fragmentsthen the team used the Norwegian rat genome as a reference to reconstruct as much of the missing rat genome as possible. Comparison of these two genomes suggested that 5% of the Christmas Island rat genome was still missing. The lost sequences included fragments of approximately 2500 of the estimated 34,000 rat genes.
The longer it has been since an extinct species and its living relative have diverged, the more likely they are to be missing genes. Mammoths and Asian elephants diverged 6 million years ago. Most of the studies have made extinction seem very simple, but it actually isn’t. According to the team it is not currently possible to make an exact replica of a woolly mammoth or a carrier pigeon, but such efforts could lead to what experts call proxy, animals similar enough to play the same role in the ecosystem. The main goal is not to make perfect photocopies, but create different and selective hybrids.
Image by harrizon from Pixabay