Scientists sequenced Ötzi's genome earlier this year, yielding a surprising result: The Iceman was more closely related to present-day Sardinians than he was to present-day Central Europeans.
But the researchers sequenced only part of the genome, and the results didn't resolve an underlying question: Did most of the Neolithic people in Central Europe have genetic profiles more characteristic of Sardinia, or had Ötzi's family recently emigrated from Southern Europe?
"Maybe Ötzi was just a tourist, maybe his parents were Sardinian and he decided to move to the Alps," Sikora said.
That would have required Ötzi's family to travel hundreds of miles, an unlikely prospect, Sikora said.
"Five thousand years ago, it's not really expected that our populations were so mobile," Sikora told LiveScience.
To answer that question, Sikora's team sequenced Ötzi's entire genome and compared it with those from hundreds of modern-day Europeans, as well as the genomes of a Stone Age hunter-gatherer found in Sweden, a farmer from Sweden, a 7,000-year-old hunter-gatherer iceman found in Iberia, and an Iron Age man found in Bulgaria.