Explanation Of The Nobel prize in Physiology Or Medicine 2022 Award

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In what happens to be a shocking announcement, Svante Pääbo, a Swedish scientist was solely awarded the prestigious Nobel prize in physiology or medicine in 2022. This is in recognition of his groundbreaking achievements in founding the field of paleogenomics. Pääbo, a specialist in evolutionary genomics and anthropology has contributed tremendously to our knowledge of the genetic ties between Neanderthals and modern humans through rigorous experiments and has "provided the basis for exploring what makes us uniquely human". Likewise outstanding is his discovery of a novel species of humans called the Denisovans using modern genomic techniques. In this article, we shall get to know about this genius and the implications of his research in physiology.

Meet Svante Pääbo

The new Nobel laureate in Physiology or Medicine, Svante Pääbo. Photo courtesy: the conversation

• Pääbo was born on 20th April 1955 in Stockholm, Sweden.

• His father is Sune Bergström who also received the Nobel prize in physiology or medicine in 1982.

• He is the founder and director of the Max Planck Institute for Evolutionary Paleontology, a leading anthropology research firm and is also considered the founder of paleogenetics.

• The rationale for his Nobel award is "for his discoveries concerning the genomes of extinct hominins and human evolution"

The detailed account of the groundbreaking discoveries by Pääbo is indeed a lengthy and complex one and perhaps too complicated. In this article, I will summarize his accomplishments and the importance of his work in physiology and health. 

It has been known since the mid-nineteenth century that other forms of humans exist. The story began with the discovery of a hominin humerus in 1956 in Neander valley, Germany. Pääbo was interested in obtaining substantial quantities of the genetic material from this skeleton for study. The success of the human genome project provided a valuable resource for the research. He was however met with several challenges.

Quick Human Evolution History

Neanderthal skull. Photo courtesy: TIME


The earliest hominin was bipedal and is the sahelanthropus. Primates diverged from Mammalia around 65 million years ago and a split from the Old World Monkeys occurred around 25 million years ago. About 20 million years ago, the Hylobatidae subfamily split from the main ape family and 14 million years ago, ponginae split off. The last common ancestor of gorillas and humans occurred around 10 million years ago. Around 6 million years ago hominins split from pan (chimpanzees). Homo appeared on the scene around 3 million years ago and Homo erectus emerged around 1.5 years ago.

The species of homo originated in Africa after which H. erectus developed and migrated out of Africa. This species led to the Neanderthals found in the Eurasian continent. Also, we should know that modern humans (Homo sapiens) appeared about 300,000 years ago and likewise left Africa so there is the possibility of interaction between us and the other species (there is evidence for this).

Challenges of Pääbo's work

DNA photo courtesy: 123RF


It is nearly impossible to obtain ancient DNA from their deposits because they are easily decomposed and are subject to chemical modifications. Well-preserved specimens can provide just trace quantities for analysis and this is very rare. Another significant setback is due to the problem of contamination by microbes, debris and even human contact. However can one obtain the DNA of species that went extinct about 40,000 years ago?

He requested and was given a sample of the bone with which he used the mitochondrial DNA (mtDNA) which was isolatable in meaningful quantities (hundreds per cell compared to 2 per nucleus). The use of mtDNA however provided limited information concerning the relationship between the Neanderthal and modern humans. He ensured that studies were performed in clean laboratories, that oligonucleotide tagging be used to identify DNA of interest and emphasized the duplication of experiments to ensure high accuracy. With the rapid development of genetic and DNA technology in later decades, he was able to develop and use advanced genomic sequencing and cloning techniques to acquire significant quantities of nuclear material and compared the sequences by alignments with people of Africa, Asia and Europe, and chimpanzees. In the 1990s, genetic studies of the Neanderthal genome because possible. The groundbreaking paper he published in 2010 revealed the genetic makeup and sequences of Neanderthal for the first time. The results revealed that the Neanderthal genome has a strong relationship to those of Europeans and Asians as compared to Africans. This suggested that Neanderthals bred with homo sapien species which migrated out of Africa (only to meet and interbreed with Neanderthals).

Discovery of Denisovans.

Photo courtesy: Nobel prize


After realizing that adequate specimens can be identified in the Altai mountains in southern Siberia. Obtaining a 40,000-year-old finger bone discovered at the site in 2008, he isolated mtDNA and performed sequencing analysis on it. Results revealed shocking information. The genome was not closely related to modern humans, Neanderthals, chimpanzees or gorillas. This gave rise to the characterization of a new species known as Denisova. The Denisovan genome was revealed to be found in the People of Eurasia and even more in South East Asia, Papua New Guinea and Pacific islands. More relationship with Denisovans was found in the later groups. Today we know that Denisova appeared around 370,000 years ago and went extinct about 30,000 years ago.

Implications And Significance Of The Research


• The research has disclosed the relationship between modern humans and Neanderthals and Denisovans. There is proof of admixture between these species and it has been confirmed that there is 1-4% of Neanderthal genes in Europeans and Asians and about 6% of Denisovans genes in the Melanesian population. This, therefore, confirms gene flow between human species forms. The fact that Africans are relatively unrelated to these extinct species offers a tougher backbone to the Out of Africa theory of human evolution. We now understand that Neanderthal DNA is found in all Non-Africans

• The knowledge explains the unique features and characteristics of humans and our genetic variations from archaic humans, especially the human brain. It has enabled us to understand the process of human evolution, uncover our close relatives and explain the mechanism of adaptation and progressive evolution in anatomical intellectual, cultural and technological contexts.

• Neanderthal genes existing in modern-day humans also explain how our immune system responds to diseases and how certain inherited alleles contribute to survival in harsh environmental conditions. The Neanderthal alleles have been implicated as risk factors for COVID-19, type-2 diabetes, lupus and other pathogenic infections.

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