Blood type distribution by country

ABO and distribution by country

  50.0% and above   40.0–49.9%   30.0–39.9%   20.0–29.9%   10.0–19.9%   5.0–9.9%

Blood group B has its highest frequency in Northern Asia and neighboring Central Asia, and its incidence diminishes both towards the west and the east, falling to single digit percentages in Spain. It is believed to have been entirely absent from Native American and Australian Aboriginal populations prior to the arrival of Europeans in those areas.

Blood group A is associated with high frequencies in Europe, especially in Scandinavia and Central Europe, although its highest frequencies occur in some Australian Aboriginal populations and the Blackfoot Indians of Montana, the US.