Remains of a 4-year-old Siberian boy, who died 24,000 years ago, were found near Lake Baikal on the upper Angara River in south-central Siberia. Creative Commons

North America’s family tree just grew a few more branches. According to new analysis of ancient DNA from a 4-year-old Siberian boy who died 24,000 years ago, Native Americans’ ancestors partly came from a population of early humans related to Europeans. This sheds new light on the origin of Native Americans, who scientists previously believed predominantly came from East Asia.

"When we sequenced this genome, something strange appeared,” lead researcher Eske Willerslev, from the University of Copenhagen, told the Nature podcast, according to the BBC. "Parts of the genome you find today in western Eurasians, other parts of the genome you find today in Native Americans - and are unique today to Native Americans."

Willerslev noted that, according to the Siberian boy’s genome -- the oldest modern human genome ever sequenced -- Native Americans were created from the intersection of two branches of people, one from East Asia and the other related to western Eurasians.

"The result came as a complete surprise to us," Willerslev told AFP. "Who would have thought that present-day Native Americans, who we learned in school derive from East Asians, share recent evolutionary history with western Eurasians?"

The 24,000-year-old remains of the Siberian boy were discovered in the 1920s near Mal’ta in a grave adorned with flint tools, pendants and other artifacts. The boy’s skeleton is housed in the Hermitage Museum in St. Petersburg. According to National Geographic, scientists analyzed a tiny sample of DNA extracted from one of the ancient Siberian boy’s arm bones. They discovered that one-third of the genome came from Eurasian descendants.

The Mal’ta-Buret’ culture existed west of Lake Baikal on the upper Angara River in south-central Siberia. They were known for their houses built of large animal bones, deer antlers and animal skins.

The first Americans came over into present-day Alaska from Siberia more than 15,000 years ago, crossing the Bering Strait on a land bridge. While the new study of the 24,000-year-old Siberian genome, published Wednesday in Nature, supports the notion that the first Americans came here from Asia across land bridges, the report portrays Native Americans as having derived in large part from Eurasian ancestors.

“The Mal'ta child represents a population of Native American ancestors who moved into Siberia, probably from Europe or west Asia,” according to an October report in Science Magazine. “Then, sometime after the Mal'ta boy died, this population mixed with East Asians. The new, admixed population eventually made its way to the Americas.”

According to the New York Times, the fact that Native Americans originated in part from Europeans could help explain two age-old questions about the people’s origins. The first is that many ancient Native American skulls were unlike those of present day Native Americans.

The second is that one of the five mitochondrial DNA lineages found in Native Americans are also present in Europeans. The new analysis could explain how Europeans who carried the specific DNA lineage moved across Siberia and intermingled with the Mal’ta culture, journeying with them into North America.