Researchers from the Federal University of São Paulo have uncovered the oldest known human viruses in Neanderthal bones dating back over 50,000 years. In a study published in a preprint on bioRxiv, the team delved into the DNA of two male Neanderthals whose remains were found in Russia’s Chagyrskaya cave, located in the Altai mountains.
Neanderthal man reconstruction, Natural History Museum, London. Credit: Paul Hudson
Their search targeted remnants of three types of DNA viruses: adenovirus, herpesvirus, and papillomavirus. Astonishingly, traces of all three viruses were found, marking them as the oldest human viruses ever discovered, surpassing even those previously identified in 31,600-year-old Homo sapiens remains.
This discovery suggests that Neanderthals may have been afflicted with the same viruses that affect modern humans today. Adenoviruses, responsible for common colds and acute gastroenteritis, along with herpesviruses like the Epstein-Barr virus linked to mononucleosis and multiple sclerosis, and papillomaviruses associated with cervical cancer, were all identified in the ancient DNA samples.
Dr. Marcelo Briones, lead author of the study, said: “Taken together, our data indicate that these viruses might represent viruses that really infected Neanderthals.” lead author of the study Marcelo Briones told New Scientist. This challenges previous notions of the health challenges faced by our ancient relatives.
3D renderings of the human papillomavirus (HPV). Credit: NIAID, via Flickr. CC BY 4.0 Deed
The study’s methodology involved comparing ancient virus sequences with modern ones to mitigate concerns of contamination. The absence of matches with recent viral strains strengthens the credibility of the results, affirming the authenticity of the ancient viral genomes recovered from the Neanderthal remains.
While the exact impact of these viruses on Neanderthal populations remains to be fully understood, the findings lend support to the hypothesis that viruses could have played a role in their extinction. Dr. Briones cautioned against attributing the extinction solely to viruses but acknowledged that their existence reinforces the hypothesis of their potential role.
Neanderthals, like modern humans, were susceptible to various pathogens, as evidenced by the transmission of diseases between humans and primates, such as chimpanzees. By reconstructing and studying these ancient viruses, scientists hope to gain insights into their reproductive and pathogenic traits.