Svante Pääbo’s findings enhanced our understanding of human evolution – Dr. Dinesh Gupta, Sr. Scientist, ICGEB

Dr. Dinesh Gupta, Sr. Scientist, ICGEB: My interest in Svante Pääbo’s work was drawn by his discovery that specific gene clusters on human genome chromosomes 3 and 12 important for antiviral signaling is associated with the risk of respiratory failure in SARS-CoV-2 infection.

I was impressed by his contributions towards the establishment of efficient processing of not-so-easy-to-handle ancient DNA samples to make them suitable for modern sequencing technologies and his analysis of DNA from different hominids, the evolutionary family of humans and their closest ancestors. The method developed by him enabled seminal discoveries based on comparative genome analysis of extinct hominins with that of homo sapiens genomes to understand human evolution.

The findings of Pääbo have greatly improved our understanding of human evolution. Pääbo established an entirely novel scientific discipline, now known as Paleogenomics. Using the methodology he developed, his research group was able to sequence the genome (DNA) of our closest extinct relatives.

His analysis concluded that the human genome consists of pieces of DNA from both extinct species due to a process known as introgression or the transfer of pieces of DNA from one species to another. Such pieces of DNA and its constituent genes are evolutionarily conserved over a long period and are called archaic gene variants.

In 2010, he published the first draft sequence of the Neanderthal genome and compared it with that of different current human genomes from other parts of the world. Based on the estimation of time required for the changes or divergence in the genomes, he concluded that the age of the Neanderthal genome was 825,000 years. By sequencing multiple Neanderthal genomes and comparing them with the current human genome, he reached striking conclusions. He found that the genes involved in skeletal morphology had changed more than expected in Neanderthal’s evolution, whereas genes involved in pigmentation and brain function had changed more in the modern human lineage.

In the same year, by sequencing a DNA sample collected from Denisova Cave in Siberia, he discovered Denisova, a new hominin distinct from Neanderthals and Homo sapiens. He also proved that Neanderthals and Denisovans inhabited Eurasia and modern humans (Homo sapiens) emerged from Africa.

With the sampling techniques developed by him and using modern DNA sequencing technologies, he is credited with several seminal discoveries over the last three decades. In recognition of his valuable scientific contributions, the Noble prize in Physiology or Medicine 2022 awarded to him is well deserved.

Dr. Dinesh Gupta, is a Group Leader of Translational Bioinformatics Groups at International Centre for Genetic Engineering and Biotechnology. [Twitter: @dineshgupt / LinkedIn: Dinesh Gupta]