South Tyrol Museum of Archaeology
Ötzi, the Snowman found in the Alps
Ancient DNA data calls into question the idea that it was the A wise man transmitting the papillomavirus to Neanderthals, and may help clarify the history of HPV in our species.
Around 5,000 years ago, the body of a man known as the “Iceman” was frozen in the Alps, in the area that today marks the border between Austria and Italy.
The resulting mummy, famous for its preserved clothing, clothing and clothing, most likely died due to an arrowhead lodged in its shoulder.
But, before deathÖtzi also suffered fractures, intestinal parasites and smoke-blackened lungs. Now, scientists admit to adding yet another problem to the list: the human papilloma virus associated with cancer, the HPV16.
In a recently pre-published in bioRxiva team of researchers reports that Ötzi and a fossil of A wise man 45 thousand years oldfound in Siberia, contain both DNA segments from the cancer-associated virus.
Study results can help determine when and how hmodern humans will have contacted the virus for the first time.
“It’s a very interesting finding,” he says. Ville Pimenoff, geneticist computing at the University of Oulu, who did not participate in the work, cited by the magazine.
The discovery reinforces the evidence that “Homo sapiens was, basically, infected by these viruses throughout its existence”, adds the researcher.
They exist hundreds of human papillomavirus, or HPVwhich settle on the skin and mucous membranes of the body. Most do not cause problemsbut about a dozen can lead to genital and throat cancers, representing about 5% of cancer cases worldwide.
These infections, and the cancers they can trigger, can be stopped vaccines available since 2006. However, there are those who fear that, given widespread vaccination, other types of HPV may occupy the “niches” left vacant.
One with more than 3000 Finnish teenagers, published in 2023 in Cell Host & Microbeconcluded that, eight years after immunizationthe types of HPV with the greatest carcinogenic potential targeted by vaccines remained largely absent, but increased the diversity of other types.
Pimenoff, who led the Finnish study, says the results underscore the importance of understand all the diversity of lineages of HPV — and understand how the virus has evolved over time.
In another, published in 2017 in Molecular Biology and Evolution, Pimenoff and colleagues rwent back in time to track HPV16responsible for many cervical cancers.
They concluded that the HPV diversified in parallel with the first hominins and that modern humans appear to have come into contact with one of the now dominant variants of HPV16 about 60 thousand years agopossibly through crosses with infected Neanderthals.
The new study fills an important gapby detecting HPV in ancient human fossils.
To search for the virus in past members of our own species, a team led by molecular biologist Marcelo Brionesa researcher at the Federal University of São Paulo (UNIFESP), downloaded publicly available DNA sequences obtained from Ötzi and a fossil known as , which appeared through erosion on a river bank in western Siberia in 2008.
Although only the body of a femur was found, radiocarbon dating indicated that the man from Ust-Ishim lived 45 thousand years ago.
Mixed with DNA from these individuals, Briones and colleagues identified tens of thousands of segments that corresponded to parts of the HPV16 genome.
But, as the fragments of ancient DNA are short and DNA only encodes four “letters” (the nucleotides A, T, C and G), it is possible that these correspondences are due to chance — that is, statistical “noise”rather than a true biological sign that those ancient genomes carried the virus.
To test this hypothesis, the team also generated and analyzed simulated sequences, to assess the probability of random sequences produce a similar pattern to that observed in ancient DNA.
The results suggest that the sequences do, in fact, come from viruses, says the study’s first author, Juliana Yazigi, a bioinformatics student at UNIFESP. “We’re pretty confident there’s a signal there. … We have the earliest evidence of HPV.” Furthermore, the viruses identified more closely matched the type of HPV that a previous study had suggested originated in Neanderthals.
To be present in Ötzi and in Ust-Ishim, two individuals separated by about 40 thousand years and 5,000 kilometersthis HPV16 variant would have to circulate in our species a long time ago. So much time that, according to Briones, it is more likely that whether it was our species that transmitted HPV16 associated with cancer in Neanderthals, not the other way around.
Supporting this scenario, in a previous project who applied the same approach to Neanderthal fossils, Briones’ team found HPV12low risk, and not HPV16, with greater carcinogenic potential.
According to the virologist Koenraad Van Doorslaerfrom the University of Arizona, by removing direct evidence of HPV16 in our species, the new conclusions “may question the idea that HPV is linked to this interbreeding event with Neanderthals.”
“Will this produce better vaccines, better treatmentsbetter cures? Probably not“, he adds. “But not all science should be about that. It should simply be about learning interesting things.”
