This is the conclusion of the latest study carried out by a team of researchers from the universities of California at San Diego and Yale (USA) and which has been published in the journal Proceedings of the National Academy of Sciences (PNAS).
The research consisted of the analysis of the entire genome of almost 1.5 million markers of genetic variation and is based on data from the “Framingham Heart Study” . The experts focused their study on 1,932 people and compared them to pairs of unrelated friends and pairs of unrelated strangers , using the same people, who were neither related nor family, in both types of samples.
The result of comparing the data revealed that the friends are genetically linked as fourth cousins or people who share great-great-grandparents, which indicates that they share approximately 1% of their genes.
“We find that, on average, we are genetically similar to our friends. We have more DNA in common with people we take as friends than we look like strangers in the same population, ”says study co-author James Fowler.
Another of the most striking conclusions of the work is that the genes that were more similar between friends seem to be evolving more rapidly than others . “The document also supports the view of humans as ‘metagenomics’, not only with respect to the microbes within us, but also the people around us. It seems that our health depends not only on our own genetic makeup but also on the genetic makeup of our friends ”, concludes Nicholas Christakis, co-author of the study.
