The Prehistory of Hep B 10,000 years of HBV and humans
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new study has traced the evolution of the hepatitis B virus (HBV) from prehistory to the present, revealing dissemination routes and changes in viral diversity. In a new paper in the journal Science, researchers uncover the evolution of HBV since the Early Holocene (roughly 12,000 years ago, when the human species began to dominate the globe) by analysing the largest dataset of ancient viral genomes produced to date.
Present-day HBV strains are classified into nine genotypes, two of which
are found predominantly in populations of Native American ancestry.
Coming to the Americas
The study provides strong evidence that these strains descend from an HBV lineage that diverged around 11,700 years ago, and was carried by some of the first inhabitants of the Americas. “Our data suggest that all known HBV genotypes descend from a strain that was infecting the ancestors of the First Americans and their closest Eurasian relatives around the time these populations diverged,” says Denise Kühnert, supervisor of the study. Kühnert is head of the Transmission, Infection, Diversification and Evolution (TIDE) Group at the Max Planck Institute for the Science of Human History in Germany.
HBV in prehistoric Europe
The study also shows that the virus was present in large parts of Europe as early as 10,000 years ago, even before the spread of agriculture to the continent. The spread of human populations in the years before present (BP), based on 918 sites (circled) in Europe and the Near East.
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HEPATITIS SA COMMUNITY NEWS 93 • March 2022
“Many human pathogens are thought to have emerged
Illustration courtesy of the Royal Society [royalsocietypublishing.org/doi/10.1098/rsif.2015.0166]
In the 21st Century, HBV causes close to one million deaths each year. Recent ancient DNA studies have shown that the virus has been infecting humans for millennia, but its past
diversity and dispersal routes remained largely unknown. The new study conducted by a large team of researchers from all around the world provides major insights into the evolutionary history of HBV by examining the virus’ genomes from the remains of 137 ancient Eurasians and Native Americans who lived at various times between 10,500 and 400 years ago. The study’s results highlight dissemination routes and shifts in viral diversity that mirror well-known human migrations and demographic events, but also show unexpected patterns and connections to the present.
