New Delhi, Aug. 4 -- the marks were smallpox lesions, and the viral DNA retrieved from their remains has now produced the first molecular proof that European colonists carried the disease to the Americas.

"Nobody would ever question that smallpox came to this hemisphere from colonization, but this proves it."

The mummies - a woman in her 30s and a man in his 20s - are believed to have been Inca. Researchers estimate both died between the late fifteenth and early seventeenth centuries, a range that places them in the colonial period that followed the Spanish arrival in the Americas. The nearly identical viral DNA found in both individuals points to a shared outbreak rather than two separate infections.

The strain recovered from the Cama...