Svante Paabo wins Medicine Nobel Prize for his work in paleogenomics

 by Mark Cyril Mercado | Reprimo

The Nobel Prize is a legacy of Alfred Nobel to those who impart the "greatest benefit to humankind" (Nobel Prize Outreach, n.d.) in the fields of Chemistry, Physics, Physiology or Medicine, Peace, and Literature. This year, the Nobel Prize in Medicine or Physiology was conferred to Svante Paabo for his discoveries and work on the genomes of extinct hominins and their link to human evolution. Svantee Paabo is a Swedish evolutionary geneticist and one of the founders of paleogenetics. One of the pioneering research that he has done in paleogenetics was the sequencing of the genome of Neanderthal, an extinct species and relative of Homo sapiens. Apart from that, he also made a sensational discovery of another extinct hominin, the Denisovan. He is currently teaching molecular evolutionary biology in Leipzig University.

Sequencing the human genome proved to be a monumental task for humanity. More seemingly impossible was the sequencing of extinct hominin genomes– yet it was accomplished by the research led by Svante Paabo. Through his analysis in paleogenetics, it was discovered that the said extinct hominins had undergone a gene transfer to the Homo sapiens aligned with the migration event in Africa, 70 000 years ago. As such, the gene flow from extinct hominins also influenced the physiology of modern humans. The discovery of the contributions and differences of the extinct Neanderthal and Denisovan genomes to the modern human genome would have a profound implication on medicine and genetics. For example, people with the version of gene EPAS1 from Denisova have advantages in high altitude environments. This gene is common in Tibetans. Moreover, the geospatial distribution of genes was also elucidated which depended on their location and evolutionary history.

During the start of Paabo’s career, he already had a vision of using the modern genetic method in studying archeological remains. But throughout his research, he encountered challenges such as the chemical modification and degradation of the DNA samples, and even contamination from bacteria and humans who managed the samples. In 1990, he continued working on archaic DNA by analyzing the genetic material in the minute mitochondria of the Neanderthal since it is present in many copies. Thus, this increased the likelihood of proper sequencing of the mitochondrial genome. Neanderthals have been found to be genetically different from the results of the comparisons between modern humans and chimpanzees.

But these could only give us limited information, so after sequencing the mitochondrial genome, Paabo took the task to another level - sequencing the nuclear genome.  As he was given the opportunity to set up the new Max Planck Institute, Paabo made it possible by improving the methods to isolate and analyze the DNA and incorporating the technical developments in sequencing technology. He also sought participation of several critical collaborators who were experts in the field of population genetics and advanced sequence analysis. Finally, in 2010, they published the draft sequence for the Neanderthal genome. The results of comparative analysis from dental evolution showed that the Neanderthals and Homo sapiens diverged, and that their recent common ancestor lived 800,000 years ago.

Through his scientific efforts and intensive research, a new field of scientific discipline has emerged – paleogenomics. Paleogenomics aims to study and reconstruct the genomic imprint of samples from fossils and remains of ancient organisms, along with the genetic changes that happened throughout evolution. This could deepen the understanding on how our own species (Homo sapiens) migrated in the past and evolved relative to other Hominins.

Reference: 

Green, Richard E., Johannes Krause, Adrian W. Briggs, Tomislav Maricic, Udo Stenzel, Martin Kircher, Nick Patterson, et al. 2010. “A Draft Sequence of the Neandertal Genome.” Science 328 (5979): 710–22. https://doi.org/10.1126/science.1188021.

Krause, Johannes, Qiaomei Fu, Jeffrey M. Good, Bence Viola, Michael V. Shunkov, Anatoli P. Derevianko, and Svante Pääbo. 2010. “The Complete Mitochondrial DNA Genome of an Unknown Hominin from Southern Siberia.” Nature 464 (7290): 894–97. https://doi.org/10.1038/nature08976.

Krings, Matthias, Anne Stone, Ralf W. Schmitz, Heike Krainitzki, Mark Stoneking, and Svante Pääbo. 1997. “Neandertal DNA Sequences and the Origin of Modern Humans.” Cell 90 (1): 19–30. https://doi.org/10.1016/S0092-8674(00)80310-4.

“Press Release: The Nobel Prize in Physiology or Medicine 2022 - NobelPrize.Org.” n.d. Accessed November 28, 2022. https://www.nobelprize.org/prizes/medicine/2022/press-release/.

Reich, David, Richard E. Green, Martin Kircher, Johannes Krause, Nick Patterson, Eric Y. Durand, Bence Viola, et al. 2010. “Genetic History of an Archaic Hominin Group from Denisova Cave in Siberia.” Nature 468 (7327): 1053–60. https://doi.org/10.1038/nature09710.