Frequency of ABO blood groups in the eastern region of Saudi Arabia

To document the frequency of the ABO and Rhesus blood groups in Saudi male donors, and to compare our results with the results of other studies in the Kingdom and elsewhere. This study included a total of 57396 male potential blood donors; 19496 blood donors between the years 1985-1989 (referred to as first period of study) and 37700 blood donors between the years 1995-1999 (2nd period). The blood donors were Saudis, coming to donate blood for various reasons to the Blood Bank Department of King Fahd Hospital of the University, Al-Khobar, Kingdom of Saudi Arabia. ABO and Rhesus blood groups from 200 Saudi females were also determined. The frequency of ABO blood groups and Rhesus status were calculated separately. Our results revealed the most common blood group was O, (52%) during the first period of study and likewise the most common blood group (51%) during the 2nd period. The lowest blood group frequency was AB (4%) and (4%) during the first and 2nd period. Rhesus positive blood donors comprised 93% and Rhesus-negative donors were 7% during the first period, while they amounted to 91.5% and 8% during the 2nd period. Overall frequency of ABO and Rhesus blood groups during the 2 periods were the following: O-positive 48% and 46%; A-positive 24% and 24.5%; B-positive, 17% and 17%; AB positive 4% and 4%; O negative 4% and 5%; A negative 2% and 2%; B-negative 1% and 2%; and AB negative, 0.23% and 0.32%. Comparison of our results with the other studies from the Kingdom and other nationalities is also presented. Our results show that the most frequent blood group in Saudis is O-positive. Blood group A is observed at a lower frequency relative to values from Western populations, whereas a significant increase in blood group B combined with a slight increase in blood group AB was recorded. Knowledge of the frequencies of the different blood groups in Saudi Arabia is very important for Blood Banks and transfusion service policies. Knowledge of blood group phenotype distribution is also important for clinical studies (for example disease association), as well as for population studies.