He came to a grim ending, but the mummified remains of a 7-year-old boy sacrificed in an Inca ritual called capacocha are allowing scientists to "learn more about the rise and extent of the Inca Empire," as the Los Angeles Times puts it. The child's frozen corpse was found in 1985 on Aconcagua, the tallest mountain beyond Asia. Science explains that the elevation and dryness gave modern-day researchers hope—followed by confirmation—there was recoverable DNA. They biopsied a 350-milligram sample from the boy's lung and found that the boy's mitochondrial genome—that's the 37 genes that specifically pass from mother to child—placed him "perfectly" within the genetic population C1b that is typical of Native Americans and that ultimately appears to come from Beringia (the land mass they crossed from Siberia to Alaska). But Science explains there are many subgroups within C1b, and the boy belonged to none of them.
Researchers, who wrote in the journal Scientific Reports that their "main aim [was] to shed light on the genetic variation existing at the time," slotted him in the new subgroup C1bi (for Inca). They ran his DNA through a genetic database and found only four matches, reports the Guardian: three people in Peru and Bolivia and one ancient member of the Wari Empire, which flourished before the Inca in Peru. While there's scant sign of C1bi now, the confirmation of two ancient C1bi samples suggests it may have been far more common, with a geneticist not involved in the study pointing out that as little as 10% of the native population survived after the Spanish reached their lands. What we have here is as if "the Inca put genetic samples in deep freeze for us," an archaeologist tells Science. The researchers are now working on the boy's nuclear genome, which hails from both parents. (The Incas may have done this to their child-sacrifice victims first.)