These genetic peculiarities, which characterize the Italians of the North and South of today, are the result of migrations, but also of the evolutionary adaptation to the different environments and climates, which have had an impact on health, enhancing some biological functions of the organism . “In Southern Italians there has been an adaptation to the higher incidence of ultraviolet rays. The genes that regulate skin pigmentation as protection have influenced the lower susceptibility to skin cancers, more common in the North”, he explains to ANSA Sazzini. In the North there has been a more metabolic adaptation, which “may have favored a lower susceptibility to diseases such as diabetes and obesity”.
To achieve these results, the researchers sequenced the genome of 40 people, representative of the biological variability of the Italian population, thus bringing to light more than 17 million genetic variants. Then they compared these data with the genetic variants of 35 other European and Mediterranean populations, and with those of some 600 human fossils from 40,000-4,000 years ago.
“The Italians of the North and South began to differentiate themselves genetically about 19,000 years ago, after the last glaciation peak, therefore before the Neolithic and Bronze Age migrations, which were thought to have influenced the most”, Sazzini continues.
According to scholars, with the increase in glacier temperatures some groups that during the glaciation had moved more to the center in ‘refuge’ regions with less rigid climate, living close to the southern Italians, moved to the north and then moved away isolating themselves progressively by the inhabitants of the South, starting the differentiation. “Another interesting fact – he concludes – is that the differences between the populations of northern and southern Europe quantitatively are the same that we observe between Northern and Southern Italy. Italy is therefore a good model for understanding what happened in Europe “.