Few of our ancestors were so poked and prodded like Neolithic Tyrolean iceman "Ötzi," cast out on an Alpine glacier in 1991. Researchers probed his stomach and bowels for traces of its last meal and analyzed his teeth for cavities. Now, an international team has sequenced his entire genome, and it is Ötzi still has some surprises.
previous computer scans had revealed severe arteriosclerosis of Ötzi, or hardening of the arteries. But the new analysis shows that Ötzi had a genetic predisposition to the disease, despite the fact that, as a hunter-gatherer, there was nothing that we currently believe to be relevant risk factors, such as excess weight, get too little exercise, and smoking or drinking. "These new data suggest that we may be less able to prevent arteriosclerosis than we thought," says cardiologist and expert mummy Gregory Thomas of the University of California, Irvine, who was not involved in the new work.
the sequencing of the entire genome also reveals more about Ötzi's ancestors. previous research has analyzed the mitochondrial DNA of Ötzi, which is inherited only through the female line, but had found some known games among modern populations. Now the sequencing of its Y chromosome puts in G2A4 uncommon haplogroup, meaning that his paternal genes are linked to a population that has left the Middle East to Europe at the beginning of the era Neolithic, about 1000 years before Ötzi lived himself.
genetic profile Ötzi mark him as being most closely related to small populations now living in the islands of Sardinia and Corsica, as well as some -unes of the most remote areas of Georgia and Russia, said geneticist Angela Graefen of the Institute for mummies and the Iceman in Bolzano, Italy, one of the leading researchers on the paper. This does not mean that Ötzi was Sardinian or Corsican, Graefen notes, but that these populations may be the closest living genetic matches hunter-gatherers who originally emigrated to Europe.
Genome analysis, published this week in Nature Communications , also contributes to our flesh picture of Ötzi the man, researchers now know that he had brown eyes, brown hair, blood type O, and shared lactose intolerance that was still the norm among Neolithic Europeans. It was also the first known carrier of Lyme disease: sequencing resulted in genes Borrelia burgdorferi bacterium responsible for the disease. Although scientists can not know if Lyme disease actually sick Ötzi during his life, discovering 60% of B. burgdorferi genome from a Neolithic media shows this pathogen has plagued humans for thousands of years. Until researchers compare the B. burgdorferi genome of Ötzi with the latest incarnations of the pathogen, they will not have a clear picture of how Lyme disease evolves . "But according to the research of other scientists are doing in the coming years, we may win many more ideas from the genome of Ötzi" says Graefen.
The new paper adds to our knowledge of the Neolithic life, said Frank Ruehli mummy expert from the University of Zurich in Switzerland. "of course, Ötzi is one person, but it is a very well preserved person well described, we have a lot additional information about already. So this is an important step. "
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