12 confirmed regions with more than 20% Rh- National frequencies are one thing, but since nations are man-made, regional data is far more interesting. The following 12 regions have been confirmed to have more than 20% rh negative residents: Basque Country Atlas Mountains, Morocco Lake Chad Gambella, Ethiopia Catalonia Silesia, Poland Scotland Northern Ireland Sinai Peninsula Rhone Valley, Switzerland Bunshouten and Spakenburg, Netherlands Karaite Jewish communities in Iraq