RESUMEN
Blood groups are genetically determined and exhibit polymorphism, where different population groups have significant difference in the frequency of each blood group. This study was conducted to determine the frequency of ABO and Rhesus D blood groups among the blood donors. A total number of 1306 blood donors attended the donor centre at SKIMS Medical College Hospital for blood donation in the year 2001-02. After each donation blood samples were collected in separate pilot tubes for the estimation of ABO and Rhesus D blood groups. The frequency of O. A, Band AB, Rhesus D positive and Rhesus D negative were calculated separately. The highest frequency among the ABO blood groups was of B (39.43%) and the lowest was of AB (8.11 %). Among the Rhesus D phenotypes. majority (93.33%) were Rhesus D positive. where as only 6.67% were Rhesus D negative. The prevalence of ABO/Rhesus D was calculated and the highest frequency was of B Rh-D positive (37.44%) followed by a Rh-D positive (28.9-+%). A Rh-D positive (19.21 %), AB Rh-D positive (7.73%), a Rh-D negative (2.90%), B Rh-D negative (1.99%), A Rh-D negative (1.37%) and AB Rh-D negative (0.38%). This study showed that most common group was B followed by a & A and 93.33% were positive for Rh-D phenotype.