A series of glycoprotein and glycolipids on the red blood cell surface constitute blood group antigens. These are A, B, AB and O in ABO blood group system and Rh in rhesus blood group system. These antigens are genetically controlled. Certain diseases have been shown to be associated with certain blood groups. In the present study an attempt is made to study the distribution of ABO and Rh. (D) blood group systems among the Brahmin caste population of Uttar Pradesh State. A total of 200 unrelated Brahmin individuals from Uttar Pradesh were studied for the phenotype and allele frequency distribution of ABO and Rh (D) blood groups. The order of occurrence of ABO phenotypes is B>O>A>AB. The corresponding allele frequencies of O, A, and B alleles are found to be 0.5790, 0.1510 and 0.2697 respectively. The allele frequency of D (0.735) is more than d (0.265). The present study was compared with the other studies reported to understand the affinity between them
