Swedish geneticist wins Nobel Prize in Physiology or Medicine

This year's Nobel Prize in Physiology or Medicine has been awarded to Swedish geneticist Svante Pääbo for his discoveries on human evolution.

Thomas Perlmann, secretary of the Nobel Committee, announced the winner Monday at the Karolinska Institute in Stockholm.

Pääbo has spearheaded research comparing the genome of modern humans and our closest extinct relatives, the Neanderthals and Denisovans, showing that there was mixing between the species.

The prizes carry a cash award of 10 million Swedish kronor (over $1.2 million Cdn) and will be handed out to the winners on Dec. 10. The money comes from a bequest left by the prize's creator, Swedish inventor Alfred Nobel, who died in 1895.

The medicine prize kicked off a week of Nobel Prize announcements. It continues Tuesday with the physics prize, with chemistry on Wednesday and literature on Thursday. The 2022 Nobel Peace Prize will be announced on Friday and the economics award on Oct. 10.

Son of a Nobel winner

While Neanderthal bones were first discovered in the mid-19th century, only by unlocking their DNA — often referred to as the code of life — have scientists been able to fully understand the links between species.

This included the time when modern humans and Neanderthals diverged as a species, determined to be around 800,000 years ago, said Anna Wedell, chair of the Nobel Committee.

"Pääbo and his team also surprisingly found that gene flow had occurred from Neanderthals to Homo sapiens, demonstrating that they had children together during periods of co-existence," she said.

This transfer of genes between hominin species affects how the immune system of modern humans reacts to infections, such as the coronavirus. People outside Africa have one to two per cent of Neanderthal genes. Neanderthals were never in Africa, so there's no known direct contribution to people in sub-Saharan Africa.

Wedell described this as "a sensational discovery" that subsequently showed Neanderthals and Denisovan to be sister groups that split from each other around 600,000 years ago. Denisovan genes have been found in up to six per cent of modern humans in Asia and Southeast Asia, indicating that interbreeding occurred there too.

"By mixing with them after migrating out of Africa, Homo sapiens picked up sequences that improved their chances to survive in their new environments," said Wedell. For example, Tibetans share a gene with Denisovans that helps them adapt to the high altitude.

Pääbo, 67, performed his prize-winning studies in Germany at the University of Munich and at the Max Planck Institute for Evolutionary Anthropology in Leipzig. Pääbo is the son of Sune Bergstrom, who won the Nobel Prize in Medicine in 1982.

University of Toronto anthropologist who has worked with Pääbo on Denisovan research:

Pääbo said he was surprised to learn of his win on Monday.

In an interview posted on the official home page of the Nobel Prizes, he mused about what would have happened if Neanderthals had survived another 40,000 years.

"Would we see even worse racism against Neanderthals, because they were really in some sense different from us? Or would we actually see our place in the living world quite in a different way when we would have other forms of humans there that are very like us but still different," he said.

The work has been years in the making. Building off of sequencing done as part of the Human Genome Project, Pääbo's team published the first draft of a Neanderthal genome in 2009. The team sequenced more than 60 per cent of the full genome from a small sample of bone, after contending with decay and contamination from bacteria.

WATCH | How Svante Pääbo's research evolved: 

Swedish geneticist wins 2022 Nobel in Physiology or Medicine

2 years ago

Duration 4:41

This year's Nobel Prize in Physiology or Medicine has been awarded to Swedish geneticist Svante Pääbo for his research comparing the genome of modern humans and our closest extinct relatives.