This year's Nobel Prize in Physiology or Medicine goes to Svante Pääbo. One of his most important scientific achievements was the decoding of the Neanderthal genome. "His work has revolutionized our understanding of the evolutionary history of modern humans," says Martin Stratmann, President of the Max Planck Society. For example, Svante Pääbo has shown that Neanderthals and other extinct hominids made a significant contribution to the ancestry of modern humans.
Svante Pääbo studied Egyptology and Medicine at Uppsala University. As a graduate student - he earned his PhD in immunology - he also demonstrated that DNA can survive in ancient Egyptian mummies, earning him professional fame as a pioneer in the new field of paleogenetics. Paleogeneticists study the genomes of ancient organisms and use them to draw conclusions about the course of evolution.
After his doctorate, Pääbo worked in the team of evolutionary biologist Allan Wilson at the University of California at Berkeley. From 1990 he headed his own laboratory at the Ludwig Maximilians University in Munich. In 1997, Pääbo became one of five directors at the newly founded Max Planck Institute for Evolutionary Anthropology in Leipzig, where he still works today.
As early as the mid-1990s, Pääbo and his team were able to decode a relatively short part of the mitochondrial DNA of a Neanderthal. Mitochondria are tiny power plants in cells that provide them with energy and have their own DNA. This DNA of the Neanderthals differed significantly from the genome of modern humans. This proved that Neanderthals are not the direct ancestors of modern humans.
As DNA sequencing methods became much more efficient in the early 2000s, Pääbo began sequencing the entire Neanderthal genome, which is present in the cell nucleus.
A gigantic puzzle
The difficulty here: after thousands of years, the bones of Neanderthals in the soil are so heavily colonized by bacteria and fungi that up to 99,9 percent of the DNA found in them comes from microbes. In addition, the small amounts of remaining Neanderthal DNA are only available in short fragments that have to be put together like a gigantic jigsaw puzzle. Many scientists believed that this task was unsolvable.
However, Pääbo's team came up with new solutions. The researchers worked under "clean room conditions" comparable to those in the chip industry. In this way, they were able to prevent them from accidentally introducing their own DNA into the experiments. In addition, they developed more efficient extraction methods that improved the yield of Neanderthal DNA. Complex computer programs that compared the DNA snippets from the ancient bones to reference genomes from chimpanzees and humans helped reconstruct the Neanderthal genome.
In 2010, Svante Pääbo and his team succeeded in reconstructing a first version of the Neanderthal genome from bones tens of thousands of years old. Comparisons of the Neanderthal genome with the genomes of modern humans revealed that when modern humans left Africa and arrived in Europe and Asia, modern humans and Neanderthals had bred together around 50.000 years ago.
Even today, around two percent Neanderthal DNA can be found in the genome of today's non-African people. This genetic contribution influenced human evolution: for example, it strengthened the immune system of modern humans, but it still contributes to susceptibility to several diseases today.
"Neanderthals are the closest relatives of modern humans," said Svante Pääbo. "Comparing their genomes with those of modern humans and those of great apes allows us to determine when genetic changes occurred in our ancestors." to colonize the whole world. However, this required a more complete knowledge of the Neanderthal genome than the team had achieved in 2010.
Get to the bottom of human origins
In 2014, the team at the Max Planck Institute for Evolutionary Anthropology succeeded in almost completely decoding the Neanderthal genome. This made a comparison with the genomes of modern humans possible. "We found around 30.000 positions in which the genomes of almost all modern humans differ from those of Neanderthals and great apes," says Pääbo. "They answer what makes anatomically modern humans 'modern' in a genetic sense as well." Some of these genetic changes may hold the key to understanding what differentiates the cognitive abilities of modern humans from those of now extinct hominids.
In the run-up to this, Svante Pääbo's team had already achieved a sensation in 2012: they decoded the genome from a small bone that they had found in the Denisova Cave in the West Siberian Altai Mountains. Distantly related to the Neanderthals, the enigmatic primordial humans contributed up to five percent of the genomes of present-day inhabitants of Papua New Guinea, Aboriginal Australians, and other groups in Oceania.
The researchers are currently working on new methods of reconstructing DNA fragments that are even more decomposed and present in even smaller quantities. The goal is to enable research into even older DNA and genetic material from parts of the world where DNA survival is even rarer due to hot and humid climates.
Like father, like son
Already Svante Pääbo's father, Sune Bergstrom, was honored with the highest scientific award: The biochemist received together with Bengt Ingemar Samuelsson and sir John Robert Vane 1982 day Nobel Prize in Physiology and medicine for their groundbreaking work on Prostaglandins and closely related biologically active substances.
The Nobel Prize in Physiology or Medicine is one of the original five prizes awarded by the Swedish inventor Alfred Nobel were donated. It has been published annually since 1901 by the Swedish Karolinska Institute forgiven and is eight million Swedish crowns (approx. 775.000 euros). On December 10th, the anniversary of Alfred Nobel's death, the highest scientific award will be handed over by the King of Sweden in Stockholm.
Awards to Svante Pääbo
Pääbo's groundbreaking research into human origins has been recognized with numerous national and international awards: Among others, he received the Gottfried Wilhelm Leibniz Prize of the German Research Foundation (1992). This was followed by the Max Delbrück Medal (1998), the Carus Medal and Prize (1999), the Rudbeck Prize (2000), the Leipzig Science Prize (2003), the Ernst Schering Prize (2003), the Louis Jeantet Prize for Medicine and the Virchow Medal (2005), the Darwin Plaque (2009), the Theodor Bücher Medal (2010) and the Newcomb-Cleveland Prize and the Prize for Biochemical Analysis from the German Society for Clinical Chemistry and Laboratory Medicine (2011).
In addition, Pääbo received HM The King's Medal from the Swedish King (2012), Gruber Prize in Genetics (2013), Learning Ladder Prize (2014). In 2015 Svante Pääbo was awarded the Lomonosov Gold Medal of the Russian Academy of Sciences and the Breakthrough Prize in Life Science, and in 2016 the Keio Medical Science Prize.
Svante Pääbo recently received the Körber European Science Prize. Every year since 1985, the Körber Foundation has honored an important breakthrough in the natural or life sciences in Europe. Excellent and innovative research approaches with high application potential are awarded. After the Körber Prize was awarded, seven prize winners – including Svante Pääbo – have so far received the Nobel Prize.
Source: Press release Max Planck Society from February 3.10.2022, XNUMX