ABO, Rhesus, and Kell Antigens, Alleles, and Haplotypes in West Bengal, India

Abstract

Background: Few studies have documented the blood group antigens in the population of eastern India. Frequencies of some common alleles and haplotypes were unknown. We describe phenotype, allele, and haplotype frequencies in the state of West Bengal, India.

Methods: We tested 1,528 blood donors at the Medical College Hospital, Kolkata. The common antigens of the ABO, Rhesus, and Kell blood group systems were determined by standard serologic methods in tubes. Allele and haplotype frequencies were calculated with an iterative method that yielded maximum-likelihood estimates under the assumption of a Hardy-Weinberg equilibrium.

Results: The prevalence of ABO antigens were B (34%), O (32%), A (25%), and AB (9%) with ABO allele frequencies for O = 0.567, A = 0.189, and B = 0.244. The D antigen (RH1) was observed in 96.6% of the blood donors with RH haplotype frequencies, such as for CDe = 0.688809, cde = 0.16983 and CdE = 0.000654. The K antigen (K1) was observed in 12 donors (0.79%) with KEL allele frequencies for K = 0.004 and k = 0.996. Conclusions: For the Bengali population living in the south of West Bengal, we established the frequencies of the major clinically relevant antigens in the ABO, Rhesus, and Kell blood group systems and derived estimates for the underlying ABO and KEL alleles and RH haplotypes. Such blood donor screening will improve the availability of compatible red cell units for transfusion. Our approach using widely available routine methods can readily be applied in other regions, where the sufficient supply of blood typed for the Rh and K antigens is lacking.

Keywords: ABO blood group; Donors; Erythrocytes; Immunohematology; Kell determination; Red blood cell antigens; Rh phenotyping; Serological typing.

Fig. 1

Blood donor demographics in West Bengal. The 1,528 donors tested in the study (black line) averaged 33.01 years old with a standard deviation of ± 9.06 years. A quarter of the donors were 26 years or younger (25% percentile), half of the donors 32 years or younger (mean, 50% percentile) and three quarters of the donors 39 years or younger (75% percentile). Female donors (gray line) represented 11% of all donors.