Blood type distribution by country

ABO and Rh 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% less than 5.0%

Blood group B has its highest frequency in the Middle East, where it ranks as the largest share of the population. In Southeast Asia its share of the population is lowest, especially in Indonesia, secondarily in East Asia, Northern Asia and neighboring Central Asia, and its incidence diminishes both towards the east and the west, falling to single-digit percentages in Netherlands, Norway, Portugal and Switzerland. 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, US.