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    New DNA analysis finds 16th-century child mummy had hepatitis B — giving evolutionary snapshot of deadly virus

    Thirty years ago, Italian scientists announced they had found what appeared to be the oldest evidence of smallpox in a 16th-century mummified child.
    Except, it wasn’t.
    A new analysis led by Canadian researchers found the child was actually infected with hepatitis B, not smallpox — making it the oldest isolation of hepatitis from any mummy or fossilized human remains. And the ancient strain appears to have barely changed over the past 450 years.
    While one historic discovery has been debunked, the new study provides a critical time stamp for the origin of a disease that is carried by 350 million people globally, and kills almost one million each year.
    Exactly when it entered human populations was unclear.
    “Given its global prevalence and the presence of related viruses in other mammals including non-human primates, it is commonly believed that the virus has existed in human populations for many thousands of years,” the team wrote in PLOS Pathogens.
    One of the best ways to understand a virus is to understand how it has evolved, said evolutionary geneticist Hendrik Poinar, of McMaster University’s Ancient DNA Centre. (Poinar was part of an international team that two years ago sequenced the genome of two woolly mammoths. He’s also the son of George Poinar, the paleobiologist whose work inspired the movie Jurassic Park.)
    “Understanding the evolution and trajectory of infectious diseases is critical for its elimination and eradication,” Poinar said.
    The new analysis is based on tiny fragments of DNA teased out of small skin and bone samples extracted from the mummified remains of an anonymous child buried in the Basilica of Saint Domenico Maggiore, one of the oldest churches in Naples, Italy.
    The Sacristy of San Domenico Maggiore housed 38 wooden coffins or “arks” with the bodies of royal Aragonese and other Neapolitan nobles.
    The two-year-old child mummy was exhumed between 1983 and 1985. Records indicate the mummy was left undisturbed from 1594.
    Scientists initially thought the toddler had been infected with smallpox because of deep, pockmark scarring on the scalp, face, arms, palms of the hands and legs. Electron microscopic images also showed egg-shaped, virus-like particles that looked like Variola virus, or smallpox, suggesting the child died of a severe form of the disease some four centuries ago, University of Pisa researchers reported in The Lancet in 1986.
    “It was an interesting paper at the time, and it certainly was of landmark,” Poinar said.
    But the earlier analysis didn’t include DNA testing.
    Last year, Poinar and his team at McMaster published a paper on a 17thcentury Lithuanian child mummy that had small pox. Afterwards, he and his team decided to analyze the Italian mummy to explore the diversity of smallpox within Europe.
    “We tried everything in our power to find smallpox in this mummy,” Poinar said. “We could not for the life of us find any.”