Inca mummy DNA confirms European smallpox origin
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- Shigeki Nakagome at Trinity College Dublin reconstructed smallpox genomes from bone samples of two Inca mummies at the Camarones 9 site in northern Chile, identifying a lineage matching early medieval and early modern European strains — the first direct molecular evidence of smallpox's introduction via European colonization.
- The two infected individuals were a woman aged 30–35 at death and an 18-to-20-year-old man whose carbon-dated remains place his death between 1492 and 1631, the period when smallpox first devastated Indigenous communities in the Americas.
- The Camarones 9 site, discovered in 1957, yielded 41 mummified bodies; the team noted that small skin lesions on the trunks of the mummies, previously attributed to chronic arsenic exposure, may in fact be smallpox pustules.
- Matthew Ward at the University of Dundee framed the finding as part of a broader catastrophe in which epidemic diseases killed perhaps 95% of the Indigenous population of the Americas and enabled European colonization.
- Constanza de la Fuente Castro at the University of Chile emphasized the ethical sensitivity of the work, noting the disturbance of original remains and loss of material during analysis are controversial for Indigenous communities, and that 'behind every DNA extraction is a person, not a data point.'
- The discovery identifies individual victims of smallpox for whom no historical record had existed, according to de la Fuente Castro, shifting the disease's footprint from large-scale outbreak accounts to named individuals.
Why it matters: The molecular evidence pins smallpox's arrival to a specific European viral lineage and a narrow window (1492–1631) that aligns with the colonization era, while identifying two previously anonymous victims buried with grave goods in northern Chile. Historians can now move beyond written accounts of mass outbreaks to trace the pathogen's actual genetic path through Indigenous populations.
