Researchers analyze DNA from people 34,000 years ago: Here’s why MS risk is so high in northwestern Europe

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A team of 175 scientists from 22 countries, including Switzerland, created the world’s largest database of ancient human DNA.

To do this, they analyzed the bones and teeth of nearly 5,000 skeletons from the Stone Age to the Bronze Age and from the Viking Age to the Middle Ages, the universities of Cambridge (USA) and Copenhagen (Denmark) wrote in a paper. The results were published in four studies Wednesday in the journal Nature.

One of the insights from this is that the origins of the increased risk of multiple sclerosis (MS) in Northwest Europe compared to other regions can be traced back to animal breeders migrating into Europe from the east about 5,000 years ago. According to the analysis, some genes that increase MS risk “migrated” to northwestern Europe with the Yamnaya pastoralist people of the Pontokaspis region, which covers parts of today’s Ukraine, southwestern Russia and western Kazakhstan.

MS is a disease in which the immune system mistakenly attacks the “insulation” of the brain and spinal cord around nerve fibers. Researchers suspect that genes that promote MS disease may have given shepherds a survival advantage. Most likely by protecting them from infections from their sheep and cattle.

“These results surprised us all. “They represent a tremendous advance in our understanding of the evolution of MS and other autoimmune diseases,” said study author William Barrie from the University of Cambridge.

The size difference between people in northwestern and southern Europe can be traced back to the Yamnaya, according to the analysis. The influence of pastoralists, which was much stronger in northwestern Europe than in southern Europe, brought about a genetic predisposition to larger body size.

In a study published on Wednesday, researchers were also able to show more connections between ancient ancestors and modern traits. For example, researchers link genetic variants associated with risk of type 2 diabetes and Alzheimer’s disease to Western hunter-gatherer ancestors.

DNA analysis of prehistoric inhabitants of Eurasia also showed that lactose tolerance (the ability to digest sugar in milk and other dairy products) emerged in Europe about 6,000 years ago. The ability to survive better on a diet rich in vegetables was engraved in the genes of Europeans at the beginning of the Neolithic Age, about 5,900 years ago.

As study leader Eske Willerslev from the University of Copenhagen (Denmark) said at a media conference about the study, the results published on Wednesday do not yet cover all 5,000 genomes analysed. According to Willerslev, published studies show how this genetic data can be used.

According to the researcher, further analyzes will be carried out with old genes in the future. They aim to uncover more information about genetic markers of autism, ADHD, schizophrenia, bipolar disorder and depression.

(SDA)

Source : Blick