A new study revealed the dispersal routes and changes in the DNA sequence of the Hepatitis B virus (Press release 8.10.2021)
Hepatitis viruses cause chronic illnesses that are difficult to treat. The most significant ones are chronic hepatitis, liver cirrhosis and liver cancer. Hepatitis B virus (HBV) is the main cause for chronic liver infections.
A study focusing on analyzing ancient viruses was conducted in an international multidisciplinary group in the Max Planck institute in Germany. 137 HBV genomes from ancient individuals living in Eurasia and America 10 500-400 years ago were analyzed. By comparing the genomes the researchers were able to analyze the dispersal routes and evolution of the HB-virus.
It seems that HBV crossed western Eurasia freely for thousands of years. This is a sign of active interactions between the eastern and western hunter-gatherers and Europe and the Middle East before the arrival of farming culture in Europe. The study also revealed that the Stone Age hunter-gatherer HBV genotypes disappeared as farming became common. It was also found out that the HBV genotypes appearing today in American natives and in the rest of the world are quite different.
Contrary to previous belief, it was revealed that HBV didn’t disperse from Africa to the rest of the world. It evolved into different genotypes, which then spread through Eurasia into Africa and Oceania, and into America with the first settlers.
This study is a great example of using viruses to examine the dispersal and origins of humans. The study was published in Science (Kocher A et al. Ten millenia of hepatitis B virus evolution. Science 2021, doi: 10.1126/science.abi5658).