Inca Mummy DNA Provides First Molecular Proof of European Smallpox

Researchers have uncovered the first direct molecular evidence that smallpox was brought to the Americas from Europe during the colonial era. By extracting ancient viral DNA from the remains of two Inca mummies, scientists have bridged a long-standing gap between historical accounts and genetic proof.

The discovery centered on bone fragments recovered from two mummified Indigenous Inca individuals at the Camarones 9 archaeological site in northern Chile. The remains belonged to an adult female, aged 30 to 35, and an adult male, aged 18 to 20. Analysis of the leg bone fragments revealed the presence of variola virus DNA. According to the research team, which included Shigeki Nakagome of Trinity College Dublin, the recovered viral genomes belong to a lineage related to early medieval and early modern European strains, having diverged from European smallpox around the 1300s.

The Historical Gap

For centuries, historians have documented the catastrophic population collapse of Indigenous peoples following European arrival. It is estimated that diseases introduced by colonizers, most notably smallpox, killed approximately 95% of the native population. These epidemics fundamentally facilitated European colonization by decimating local populations. However, until this study, these claims relied almost exclusively on written historical records and circumstantial evidence rather than direct genetic material from the victims themselves.

Implications for Science

This finding provides a definitive biological link between European colonization and the spread of the variola virus in the Americas. By establishing a genetic baseline, researchers can now better understand how the virus evolved as it moved through non-immune populations in the 16th and 17th centuries. The molecular confirmation validates the scale of the biological impact of the colonial encounter, transforming a historical narrative into a verified scientific fact.

Future Research

With this genetic marker established, scientists may now look to other archaeological sites to map the precise trajectory and speed of the virus's spread across the continent. While the molecular evidence is now clear, researchers continue to examine the physical remains of the Camarones 9 individuals to further understand the pathology of the disease in ancient populations. The study marks a significant milestone in paleogenomics, proving that the remnants of ancient pathogens can survive in bone tissue long enough to rewrite the scientific understanding of colonial history.