2023-08-16 18:00:07
The genetic composition of most of today’s Europeans is mainly due to the mixture of three ancestral groups: the Hunter-gatherers Westerners gradually merged with the first farmerswho migrated from Anatolia about 8,000 years ago and were later joined by the steppe herders from Eastern Europe, approximately 4,900 years ago.
He Tyrolean Neolithic Iceman “Ötzi”, discovered by mountaineers in the Alps in 1991, has been extensively studied as it is one of the best preserved ice mummies and by far the oldest. Until now, numerous studies had been carried out on her to find out who she was, including investigations into her genomic and ancestral makeup.
In 2012, a genome was generated that offered new insights, but was heavily contaminated with current human DNA. In this way, it was considered that it was a light-skinned and hairy male. Since the first studies, not only have the sequencing technologiesbut many more genomes of other prehistoric Europeans have been fully deciphered, often through bone finds.
Now, new research from a high-coverage analysis of the mummy’s genome offers some surprises. For starters, it shows that Ötzi had dark skin and eyes and was bald.
“In the new study we generated a high-coverage genome from advanced sequencing technology that allows in-depth investigation of possible phenotypic traits. The analysis of the ancestry of the genomes informs us about the genetic origin of a mummy, and the examination of the alleles related to the phenotype offers us information about the possible phenotypic traits before death”, he points out to SINC To Moneyresearcher at the Max Planck Institute for Evolutionary Anthropology (Germany), who co-leads the work.
We generate a high coverage genome from advanced sequencing technology that allows in-depth investigation of possible phenotypic traits
Ke Wang, a researcher at the Max Planck Institute
These phenotypic traits contrast sharply with previous reconstructions. “The mummy itself is dark and has no hair,” he explains. Johannes Krause, also a scientist at the Max Planck Institute. Therefore, these findings suggest that when he was alive, the iceman resembled the mummy today. “It is remarkable how the reconstruction is biased by our own preconceived idea of a stone age human from Europe”, highlights the scientist.
“It was previously thought that the mummy’s skin had darkened during its preservation in ice, but presumably what we see now is actually very much Ötzi’s original skin color. Knowing this, of course, is also important. important for proper preservation of the mummy”, indicates the anthropologist Albert Zinkco-author of the study and director of the Eurac Research Institute for Mummy Studies in Bolzano (Italy).
As a mature man, it is also likely that he no longer had thick, long hair on his head but, at best, a sparse crown. In fact, his genes show a predisposition to baldness. “This is a relatively clear result and could also explain why almost no hair was found on the mummy,” says Zink.
Genes for increased risk of obesity and type 2 diabetes were also found in Ötzi’s genome, but it is likely that these factors did not come into play thanks to his healthy lifestyle. “There are risk alleles related to both diseases in her genome,” Wang explains.
Ötzi’s ancestry
Comparing Ötzi’s genetic code with that of his contemporaries, they also found that, among the hundreds of early European peoples who lived at the same time as Ötzi and whose genomes are now available, the Tyrolean Iceman genome has more ancestors in common with early Anatolian farmers than any of their European counterparts from the 4th millennium BC
“Ötzi came from a relatively isolated population who had very little contact with other European groups. This population has little hunter-gatherer ancestry and no steppe-related ancestry,” Wang explains.
Ötzi came from a relatively isolated population that had very little contact with other European groups.
To Money
Previous work suggested a close genetic affinity between Ötzi and modern Sardinians. But the researchers now say they reached those conclusions before more human genomes were available.
“We were very surprised to find no trace of Eastern European steppe herders in this most recent analysis; the proportion of hunter-gatherer genes in Ötzi’s genome is also very low. Genetically, his ancestors appear to have come directly from Anatolia without mixing. with groups of hunter-gatherers,” says Krause.
In fact, the ice man has more than one 92% Anatolian ancestry of the first farmers. The results also suggest that the Alps were a genetic barrier. Consequently, according to the scientists, the population of this iceman did not exchange many genes with the peoples north and west of the Alps.
What is not yet clear is whether or not Ötzi is representative of the populations of their time and place of origin. To answer that question, future studies will have to look at more individuals from the same region.
Reference:
Wang et al. “High coverage genome of the Tyrolean Iceman reveals unusually high Anatolian Farmer ancestry”. Cell Genomics.
Fuente: SINC
Rights: Creative Commons.
#Iceman #Ötzi #bald #darkskinned #Anatolian #descent