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New study traces evolution of hepatitis B virus from prehistory to present

Main distribution of present-day HBV genotypes. Reprinted with permission from Kocher et al., Science [Volume #]:[first page of article] (2021)

Analyzing the largest dataset of ancient viral genomes produced to date, researchers uncover the evolution of the hepatitis B virus (HBV) in a new paper in the journalScience.

A scientist sampling a tooth in the ancient DNA laboratory of the Max Planck Institute for the Science of Human History (Photo Credit: Raffaela Bianco).

Mirjana Roksandic博士,Yadira Chinique de Armas博士和Silvia Hernandez Godoy博士 - Uwinnipeg的所有成员Caribbean Research Institute– are part of a global team of researchers providing major insights into the evolutionary history of HBV by examining the virus’ genomes from 137 ancient Eurasians and Native Americans dated to between 10,500 and 400 years ago.

“These results highlight dissemination routes and shifts in viral diversity that mirror well-known human migrations and demographic events, as well as unexpected patterns and connections to the present,” said Roksandic.

HBV and the peopling of the Americas

The hepatitis B virus (HBV) is a major health problem worldwide, causing close to one million deaths each year. Recent ancient DNA studies have shown that HBV has been infecting humans for millennia, but its past diversity and dispersal routes remain largely unknown.

当今的HBV菌株分为9种基因型,其中两种主要在美国原住民血统的种群中发现。该研究提供了有力的证据,表明这些菌株来自于更新世末端的HBV谱系,并由美洲的一些第一批居民携带。

“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, leader of the潮research groupand supervisor of the study.Caribbean Research Institute

史前欧洲的HBV

The study also shows that the virus was present in large parts of Europe as early as 10,000 years ago, before the spread of agriculture to the continent.

“许多人类病原体are thought to have emerged after the introduction of agriculture, but HBV was clearly already affecting prehistoric hunter-gatherer populations,” says Johannes Krause, director of the Department of Archaeogenetics at the马克斯·普朗克进化人类学研究所and co-supervisor of the study.

After the Neolithic transition in Europe, the HBV strains carried by hunter-gatherers were replaced by new strains that were likely spread by the continent’s first farmers, mirroring the large genetic influx associated with the expansion of farming groups across the region.

These new viral lineages continued to prevail throughout western Eurasia for close to 4,000 years. The dominance of these strains lasted through the expansion of Western Steppe Herders around 5,000 years ago, which dramatically altered the genetic profile of Europeans but remarkably was not associated with the spread of new HBV variants.

The collapse and re-emergence of pre-historic HBV

One of the most surprising findings of the study is a sudden decline of HBV diversity in western Eurasia during the second half of the 2nd millennium BCE, a time of major cultural shifts, including the collapse of large Bronze Age state societies in the eastern Mediterranean region.

“This could point to important changes in epidemiological dynamics over a very large region during this period, but we will need more research to understand what happened,” says Arthur Kocher, lead author and researcher in thegroup.

All ancient HBV strains recovered in western Eurasia after this period belonged to new viral lineages that still prevail in the region today. However, it appears that one variant related to the previous pre-historic diversity of the region has persisted to the present. This prehistoric variant has evolved into a rare genotype that seems to have emerged recently during the HIV pandemic, for reasons that remain to be understood.


UWinnipeg’sCaribbean Research Instituteis dedicated to advancing research in the circum-Caribbean region through the examination and reconstruction of the precolonial history of the Caribbean region from local, regional, and continental perspectives.

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