Ötzi, the 5,300-year-old mummy found murdered high in the Alps with an arrow in his back, is a prehistoric celebrity who attracts 300,000 visitors a year to his custom cooling chamber in the South Tyrol Museum of Archaeology in Bolzano, Italy. Years of studies have revealed much about the Iceman, from his last meal—dried ibex and deer meat with einkorn wheat—to the distant Tuscan origins of his copper ax. But while the wizened mummy is extraordinarily well preserved for its age, it gives little impression of how Ötzi would have appeared in life. Now, a detailed genetic study has revealed much more about what the Iceman looked like—and traces the Copper Age corpse’s ancestral lineage back to Anatolia, an area that is now the Asian portion of Turkey.
Scientists have newly sequenced Ötzi’s genome a decade after an earlier effort, using modern techniques and comparative data to produce a much higher-quality result than ever before. The study published Wednesday in Cell Genomics reveals that Ötzi had dark eyes and skin pigmentation darker than that commonly seen among modern inhabitants of Greece or Sicily, though he’s previously been depicted with lighter skin more akin to that of Europeans living in the Alps today. And contrary to most artists’ interpretations, it also appears that he suffered from an age-old affliction still troublesome today—he was going bald.
The study also used comparisons with other ancient individuals’ DNA to suggest that the Iceman is descended, in large part, from the Anatolian agriculturalists who first brought farming to Europe about 9,000 years ago, through what is now Turkey into Greece and the Balkan Peninsula. Ötzi’s genes show little mixing with the hunter-gatherer populations already living in Europe during that time, suggesting that his community was small and relatively isolated in their beautiful but remote alpine environment.
“The Iceman genome was the second or third (depending whether you count Neanderthals) ancient human genome ever published,” says Iain Mathieson, a population geneticist at the University of Pennsylvania, who wasn’t involved in the new study. Mathieson called the 2012 effort to sequence Ötzi's genome a remarkable achievement, but he noted that technology has since improved by leaps and bounds. “From the perspective of the now more mature field, it’s nice to see people going back, producing higher-quality data and doing justice to this iconic individual.”
In 1991, a group of German hikers accidentally discovered Ötzi, emerging from the ice, high in the Tyrolean Alps along the Austrian-Italian border. His remains created instant intrigue even after 5,300 years—the mysterious mummy had been shot in the back with an arrow that entered his left shoulder and pierced an artery, causing him to bleed to death. But why was he killed? And how did his body survive in such amazing shape?
Ötzi’s preservation is so unusual he was first thought to be a far more modern corpse. While it was once believed that the uniquely fortunate timing and location of his death immediately resulted in his permanent burial below snow and ice, it now seems that he was exposed to the elements during various eras. That theory makes more such discoveries possible or perhaps even likely as Europe’s glaciers melt. (Other human bodies, horse remains and even centuries-old skis have emerged from alpine glaciers since Ötzi was found.)
The brown eyes, brown hair and darker skin tone suggested by Ötzi’s genes appear to be typical of Europe’s Neolithic Anatolian migrants, according to genetic research on other ancient skeletons. “The results about pigmentation are what we would expect given what we know about other nearby populations,” said Mathieson. These groups rather quickly adapted to life in Europe, where less sunny weather favored skin that could more easily synthesize vitamin D from sunlight, so genomes show that Europeans had much lighter skin tones by the Bronze Age.
Researchers often assumed that mummification and thousands of years in the elements stripped Ötzi’s skin of hair. In artists’ reconstructions, he is invariably hirsute. “All of them are shown with a lot of hair and it usually looks bit wild, although we know that people used combs very early in history,” says Albert Zink, who heads the Eurac Institute for Mummy Studies in Bolzano and is a co-author of the new study. Zink reports that Ötzi, who was in his mid-40s when he was killed, carries genetic alleles related to male pattern baldness—suggesting that contrary to our modern assumptions, he may have looked like many other balding middle-aged men. “I think there’s still a little bit of that long-haired caveman idea in our minds,” Zink says.
The study also sheds light on Ötzi’s ancestors. In recent years, geneticists have used ancient DNA to map out the migrations that populated Europe, including those that brought Ötzi’s forebears to the Alps. Starting around 7000 B.C.E., farmers migrated from Anatolia across the Mediterranean, and through the Balkans, following the Danube River into Central Europe, bringing agriculture along with them. People of this early Neolithic farmer ancestry eventually mixed, at least intermittently, with local hunter-gatherers so that by the end of the fourth millennium B.C.E., populations across much of Europe showed DNA from both groups, which is still seen in modern Europeans.
Ötzi’s ancestry is nearly entirely that of those Anatolian farmers—more than 90 percent. In fact, his genome shows the highest proportion of this ancestry yet found among Europeans of his era.
“It really looks like he lived in a quite isolated environment in the Alps, with not a lot of movement going on in the area, which makes sense because it wasn’t easy to reach and the population density for sure was not very high,” says Zink, noting that hunter-gatherers who lived in the region were also not present in large populations. This would explain why Ötzi had so much ancestry from his Anatolian farmer forebears and relatively little genetic influence from the region’s hunter-gatherer populations. “It matches the environment he lived in at that time.”
The Alps are a formidable natural barrier, and Ötzi’s genes suggest that his population never did mix much with the peoples living north or west of the formidable mountain range. The relatively small hunter-gatherer influence in Ötzi’s genome only appears a few dozen generations before Ötzi’s own time, meaning that Europe’s earlier hunter-gatherer peoples likely survived south of the Alps until perhaps 5000 or 4000 B.C.E.
The new study also makes it clear that Ötzi isn’t related to herding peoples from the Russian Steppe who migrated west and helped to shape European populations. Earlier DNA studies that had suggested Ötzi had Steppe ancestry were likely fouled by contaminated from modern DNA, which still retains that ancestral link.
“It’s great that there is now a high-quality genome for Ötzi, especially [since] the previously reported one from 2012 was about 7 percent contaminated with modern DNA,” says geneticist David Reich, of Harvard University, who wasn’t involved in the research. “It is wonderful to have good-quality data from this unique individual.”
The mummy shows the physical scars of a tough life, including broken ribs, a broken nose, cavities and intestinal parasites. His right hand is cut nearly to the bone between the thumb and forefinger, perhaps from blocking the blow of a blade in the days before he died. And the Iceman’s genes also reveal some intriguing hidden information about his health.
Ötzi had a genetic predisposition to cardiovascular diseases. “This is interesting, because it was long believed to be a more modern disease of civilization,” Zink says. “But it seems to be something that depends not only on your lifestyle but also on your genetic makeup.” Ötzi was
also predisposed for Type 2 diabetes and obesity, but these never developed, because his active lifestyle and diet trumped his genetic predispositions.
Because of his preservation, Ötzi is a unique representative of his time who reveals to us, among other things, the world’s oldest-known tattoos—61 of them—and warm clothing of the period that is both functional and, in its way, stylish.
But was he an outlier in his own day? Or a typical example of the people living in the region 5,000 years ago? The study isn’t able to say much about Ötzi’s community during the time of his life and dramatic death. That can only be known if scientists find more individuals in the region who also lived during Ötzi’s era—an effort that is well underway.
Zink is part of a group working on collecting genetic data from Ötzi’s contemporaries in South Tyrol and Trentino in Italy. Although they’ve yet to find another mummy like him, they now have located about 100 skeletons to help flesh out a picture of the ancient groups among which the Iceman lived. “We hope to learn more,” Zink says, “to get a better understanding of whether he was a typical individual of that time or maybe somehow different from the others.”