Swedish biologist Svante Papu Mark this Monday with The Nobel Prize in Medicine and Physiology 2022. This was announced by the Karolinska Institutet, which highlighted his discoveries about him Genomes of extinct humans and human evolution.
Svante Papu He succeeded in sequencing the genome of a Neanderthal, a relative of extinct humans. He also made the discovery of a previously unknown hominin, Denisova.
In addition, Pääbo found that there was Gene transfer from these humans, now extinct, to sane man After migration from Africa about 70 thousand years ago. This ancient gene flow into modern humans has physiological relevance today, affecting, for example, the way our immune systems react to infection.
Pääbo’s research gave rise to a new scientific discipline: paleontology. The Nobel Committee confirmed in its announcement of the award The biologist’s discoveries “provide the basis for exploring what makes us uniquely human.”
in 2021 Nobel Prize in Medicine Awarded to researchers David Julius and Erdem PatbutianDiscoverers of cell receptors that humans use to sense temperature and touch.
Homo sapiens first appeared in Africa about 300,000 years ago, while Neanderthals – our closest relatives – evolved outside Africa and populated Europe and western Asia about 400,000 years ago until 30,000 years ago, when they became extinct.
About 70,000 years ago, groups of Homo sapiens migrated from Africa to the Middle East and spread to the rest of the world. Homo sapiens and Neanderthals coexisted in most parts of Eurasia for tens of thousands of years.
Babu He sought to use modern genetic methods to study the DNA of Neanderthals. However, he realized the complexity of this, because over time the DNA is chemically modified and degrades into short fragments. Thousands of years later, only traces of DNA remain, and what remains is heavily contaminated with DNA from modern bacteria and humans.
So, Pääbo Methods for studying Neanderthal DNA began to be developedan effort that lasted several decades.
In 1990, the researcher began analyzing the DNA of Neanderthal mitochondria, the organelles in cells that contain their own DNA. The mitochondrial genome is small and contains only a fraction of a cell’s genetic information, but it exists in thousands of copies, which increases the chances of success.
He managed to sequence a region of mitochondrial DNA from a 40,000-year-old bone And for the first time a sequence has been accessed from an extinct relative.
Then Pääbo began trying to sequence the nuclear genome of Neanderthals. He has achieved it. In 2010, he was able to publish the first sequence of the Neanderthal genome. Comparative analyzes showed that The most recent common ancestor of Neanderthals and Homo sapiens lived about 800,000 years ago.
Discovering a Denisovan
In 2008, aFragment of a 40,000-year-old finger bone In Denisova Cave in the southern part of Siberia. bone It contained exceptionally well-preserved DNA, which the Pääbo team sequenced.
The results showed that the DNA sequence was unique compared to all known sequences from Neanderthals and modern humans. Pääbo discovered a previously unknown species of hominid, which he named Denisova.
Karoliska Institute noted that Pääbo’s discoveries have generated a A New Understanding of Evolutionary History.