LEIPZIG, Germany — Swedish scientist Svante Paabo won the Nobel Prize in Medicine on Monday for his discoveries about human evolution that revealed the secrets of Neanderthal DNA that helped us understand what makes humans unique and have provided key information about our immune system, including our vulnerability to severe COVID-19.
The techniques developed by Paabo have allowed researchers to compare the genome of modern humans with that of other hominins – the Denisovans as well as the Neanderthals.
“Just like you do an archaeological dig to uncover the past, we kind of dig into the human genome,” he said at a press conference organized by the Max Planck Institute for Evolutionary Anthropology in Leipzig.
While Neanderthal bones were first discovered in the mid-19th century, it was only by understanding their DNA – often called the code of life – that scientists were able to fully understand the connections between the species. .
This included the time when modern humans and Neanderthals diverged as a species, around 800,000 years ago.
“Paabo and his team also surprisingly found that gene flow occurred from Neanderthals to Homo sapiens, demonstrating that they had children together during periods of coexistence,” said Anna Wedell, chair of the Nobel Committee.
This transfer of genes between hominin species affects how the immune system of modern humans responds to infections, such as the coronavirus. People outside of Africa have 1-2% Neanderthal genes. Neanderthals were never in Africa, so there are no known direct contributions to the people of sub-Saharan Africa.
Paabo and his team successfully extracted DNA from a tiny finger bone found in a cave in Siberia, leading to the recognition of a new species of ancient humans they called Denisovans.
Wedell called it “a sensational discovery” which showed that the Neanderthals and Denisovans were sister groups that separated around 600,000 years ago. Denisovan genes have been found in up to 6% of modern humans in Asia and Southeast Asia, indicating that interbreeding occurred there as well.
“By mingling with them after migrating out of Africa, Homo sapiens recovered sequences that improved their chances of surviving in their new environment,” said Wedel. For example, Tibetans share a gene with Denisovans that helps them adapt to high altitudes.
Paabo said he was surprised to learn of his victory and initially thought it was an elaborate prank by colleagues or a call about his summer residence in Sweden.
“So I was just having the last cup of tea to pick up my daughter from her nanny where she spent the night, and then I got this call from Sweden,” he said in an interview on the Nobel Prizes homepage. “I thought, ‘Oh the lawnmower’s broken or something'” at the summer house.
He also pondered what would have happened if Neanderthals had survived another 40,000 years.
“Would we see even worse racism against Neanderthals, because they were really different from us in some way? Or would we actually see our place in the living world in an entirely different way when we have other forms of humans out there who look a lot like us but are still different,” he said.
Paabo, 67, completed his award-winning studies at the University of Munich and the Max Planck Institute. During the celebrations after the press conference in Leipzig, colleagues threw him into a pool of water. Paabo took it humorously, splashing his feet and laughing.
Paabo’s father, Sune Bergstrom, won the Nobel Prize in Medicine in 1982, the eighth time a laureate’s son or daughter has also won a Nobel Prize. In his book “Neanderthal Man: In Search of Lost Genomes,” Paabo described himself as Bergstrom’s “secret extramarital son” — something he also mentioned briefly on Monday.