"Perhaps it's time to reconsider how we see Neanderthals."

 January 12, 2023 5.00 GMT

The Swedish scientist discusses his Nobel Prize triumph, his laureate father, and the sensitive side of early man.

                                   The number of visitors to Svante Pääbo's office has increased significantly since it was announced that he would receive a Nobel prize. An unfriendly neanderthal skeleton is stationed at the entrance, acting as a doorman to check on them. Its right lower arm is gone, and its left hand is holding a white celebration balloon.

Pääbo pats the skeleton's skull and chuckles, "Unfortunately my son broke it off once.

The Swedish geneticist is still suffering from the shock of being named the Nobel Prize for Medicine or Physiology (the award spans both subjects) in October on the day the Guardian visits. On his desk, there is a bottle of champagne and congratulations notes from friends and coworkers. In a rare interview over coffee and shortbread, he confesses: "To be honest, all the attention I've been getting is a bit of a strain. However, it's a lovely weight, and I am aware that no one will feel sorry for me.

His coworkers tried their best to prevent the prize from going to his head at the Max Planck Institute for Evolutionary Anthropology in Leipzig, eastern Germany, which the Swedish researcher founded 25 years ago and where he has constructed a climbing wall in the foyer and a sauna on the roof.

It's sort of a tradition here, so they gave me champagne before throwing me into the pond outside. It was chilly, but they were very nice and took my glasses and phone first.

He claims that, to be fair to them, "they were in a joyful mindset. Since our discipline has never before received a Nobel prize, this honour belongs equally to them and to me.

Pääbo is credited for altering the history of humanity by doing what was long thought to be impossible: extracting ancient DNA and decoding the Neanderthal genome. His discovery of Denisova, a previously undiscovered hominim (the term refers to modern and extinct humans, as well as our immediate ancestors), and his determination that a gene transfer between Neanderthals and Homo sapiens had occurred about 70,000 years ago have revolutionised our understanding of the past. He also gave rise to the scientific field of paleogenetics.

The discovery that there are far fewer genetic variations between two randomly selected modern humans — around 3 million — than between Neanderthals and all other modern humans was one of the first of many shocks in his research. Our task is to determine which of those 30,000 are the most significant since they reveal what is essentially human about us, he claims.

Living humans include at least 50% of the Neanderthal genome, and according to Pääbo, up to 60% to 70% of it. Which implies that Neanderthals are actually still living among us and are not truly extinct.

Pääbo admits that before his addiction, he had a pastime of sorts. "When I was younger, I aspired to become an Egyptologist and archaeologist. In Sweden, where I resided, I conducted covert, personal excavations. It was vital that he travel to Egypt with his mother, who had a significant impact on his life. However, he discovered that his conception of Egyptology was "much too romantic" once he began studying it. He then changed careers to medicine and earned a PhD in molecular biology.

"I realised there were developing techniques that allowed you to extract DNA from an organism, grow the bacterium, and analyse it. I believed that doing this with Egyptian mummies wasn't that far off.

In order to avoid offending his thesis adviser, he began his experiments in secret on the weekends. However, when Pääbo presented his findings, the adviser was incredibly supportive.

It found out that old samples could be used to extract DNA, but they were severely polluted with bacteria and other DNA sources. He then focused his efforts on creating more complex extraction techniques, which eventually allowed him to recover DNA from Neanderthals, Denisovans, and other hominids after years of trial and error.

The tale of scientific accomplishment is also one of great human struggle. "My father had two families; we belonged to the secret family while the other belonged to the official family. On Saturdays, my father would arrive, meet with my mother and me for coffee or lunch, and then go once again.

He claims that his late mother Karin, who passed away in 2013, would have been "happy and pleased" about his win. She fled the Soviet invasion of Estonia by moving to Sweden in 1944, and she overcame language and financial obstacles to pursue a career in chemistry.

Pääbo claims that his own scientific career was not greatly influenced by the fact that his father, biochemist Sune Bergström, received the Nobel prize for physiology or medicine in 1982 for his research on prostaglandins. "Only inasmuch as my mum got to know him via her job. She actually passed over to me a profound passion with science. She greatly fueled my interest and helped me transition from the medical field to the natural sciences. She had by far the most impact.

He was a graduate student in Uppsala when his father won the prize in Stockholm and watched the event on television.

Only a small number of people even recognised we were linked because I had a different surname from him, he claims. It hurt him more that his other, "official" son was unaware of us than it did having to keep his renowned father a secret from his peers. We got into a lot of heated arguments over it. I even vowed to track down his family and explain the situation to them. My father thus promised to notify them, but that never happened," the boy remembers.

When Bergström passed away in 2005, he claimed to have informed his father's other relatives in 2014. "My half-brother only found out about me then. Fortunately, he changed, and things are OK with us now," Pääbo stated.

Pääbo compares his study to that of an archaeologist, noting that "our excavations are in genomes," and claims that his own curiosity is the primary thing driving him.

The data he and his team have discovered provide us with a brand-new frame of reference for comprehending our evolutionary history, which could have a number of advantages, "including enabling a greater understanding as to what makes us uniquely human and how evolution influences our biology today," he says.

Pääbo emphasises how shocking it was to learn that those who inherited a certain Neanderthal chromosomal variation had a twofold increased risk of dying from Covid infection.

He claims that based on the frequency of the risk variant and official coronavirus mortality figures, "we may estimate that this Neanderthal mutation is responsible for 1.1 million more coronavirus fatalities." Southern Asia is where this variation is most frequently seen.

Another unexpected finding has to do with how we perceive pain. Pääbo was able to determine that persons with a particular Neanderthal mutation are more likely to feel pain and to age more quickly using information from the UK's biobank, the biggest biomedical database in the world that holds the genetic information of about 500,000 of the nation's population. Pääbo jokes, "Perhaps it's time to reconsider our perception of Neanderthals as brutal people. Possibly they were quite sensitive after all.

Other substantial research initiatives include a wide range of topics, including HIV susceptibility and progesterone receptors' impact on pre-term births and miscarriages. Here, it has been demonstrated that having a Neanderthal variation can prevent miscarriage.

The 67-year-old claims, "Today there are three good quality Neanderthal genomes in the public domain, and I can tell you that there are more on the road," adding that he has put off retiring for the time being.