I don't think this is credible. (And in some places it's semi-crazy.) Just off the top of my head, the population that has the most DNA in common with Neanderth

I don't think this is credible. (And in some places it's semi-crazy.) Just off the top of my head, the population that has the most DNA in common with Neanderthals is not Basques but Tuscans. This article summarizes a much more plausible theory: https://www.bbc.com/news/science-environment-34175224 https://www.bbc.com/news/science-environment-34175224