Last updated May 15, 2018 at 10:18 am
Discovery may establish origin and early history of HBV, which has now infected 257 million people worldwide.
Traces of the hepatitis B virus – including strains that are now extinct – have been uncovered in human tissue samples dating back to the Bronze Age.
Using samples from a vast area of the Eurasian steppes spanning about 8,000 km from Hungary to northeastern China, researchers from the University of Cambridge sequenced the genomes of 304 humans, who lived between about 200 and 7,000 years ago.
They found evidence of HBV infections in 25 individuals, spanning a period of almost 4,000 years.
The authors recovered 12 full or partial HBV genomes that they analysed together with contemporary human and non-human primate HBV genomes.
The ancient HBV genomes were found in regions where the virus is not found in the present-day.
In a separate paper, Eske Willerslev and colleagues studied genomic data from sequenced the genomes of 137 ancient humans from the same region.
They then studied genomic data from 502 individuals from present-day self-reported ancestries across Central Asia, Altai, Siberia and the Caucasus.
The findings shed light on the population history of the region, suggesting a gradual transition from Bronze Age pastoralists of Eurasian ancestry towards mounted warriors with primarily East Asian ancestry.
Both studies are reported in Nature this week.