According to the study, the Iceman’s maternal line appears to have originated and died out in the eastern Italian Alps. On the other hand, his paternal lineage is still observed in Europe, and new male relatives, alive and well, may be possibly added to the list of the mummy’s descendants.
The announcement comes a week after researchers published the results of a genetic analysis which established the Copper Age man was infected with Helicobacter pylori, the pathogen that gives people gastritis and stomach ulcers.
Found in 1991 in a melting glacier in the Oetztal Alps (hence the name), the mummy is one of the most heavily investigated human corpses of all time.
Scientists discovered that Oetzi had brown eyes and very bad teeth, was lactose intolerant, had a genetic predisposition for an increased risk for coronary heart disease and probably had Lyme disease.
It’s certain he died a violent death: In 2007, CT scans showed that an arrowhead had lacerated his left subclavian artery, leading to fast bleeding.
In 2012 a complete analysis of the mummy’s Y chromosome, which is transmitted from fathers to their sons, revealed that Oetzi’s paternal genetic line, named G2a, is still present in modern-day populations.
Questions remained about the Iceman’s maternal lineage, which is named K1f.
“The mummy’s mitochondrial DNA [which is passed from the mother's to her offspring] was the first to be analyzed in 1994,” Valentina Coia, a biologist at the European Academy of Bolzano/Bozen (EURAC), said.
“It was relatively easy to analyze and — along with the Y chromosome — allows us to go back in time, telling us about the genetic history of an individual. Despite this, the genetic relationship between the Iceman’s maternal lineage and lineages found in modern populations was not yet clear,” she said.
To understand whether Oetzi’s genetic maternal line has left its mark in current populations, Coia and EURAC colleagues, in collaboration with the Sapienza University of Rome and the University of Santiago de Compostela, compared the mummy’s mitochondrial DNA with that from 1,077 individuals belonging to the K1 lineage.
Among the samples, 42 originated from the eastern Italian Alps -- in genetic continuity with the mummy.
The comparison revealed that neither the Iceman’s lineage nor any other evolutionarily close lineages are present in modern populations, suggesting that Oetzi’s maternal genetic branch is probably extinct.
“Interestingly, there is a contrast between the Iceman’s maternal and paternal genetic heritage,” the researchers wrote in Scientific Reports, an online open access journal of the Nature group.
“How can this pattern be explained?” they wondered.
To investigate this point, Coia and colleagues compared Oetzi’s mitochondrial DNA and Y chromosome with available data from numerous ancient samples found at 14 different archaeological sites throughout Europe.
It emerged that the Iceman’s paternal lineage was very common in different regions in Europe during the Neolithic age, while his maternal line probably existed only in the eastern Alps.
Putting together the genetic data on the ancient and modern samples, the researchers were able to reconstruct a possible scenario to explain the Iceman’s genetic history: Oetzi’s paternal lineage, G2a, is part of an ancient genetic substrate that arrived in Europe from the Near East with the migrations of the first Neolithic peoples some 8,000 years ago.
Migrations after the Neolithic Age in Europe partially replaced G2a with other lineages, except in geographically isolated areas such as Sardinia.
Read more at Discovery News
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