Phenotype and Allele Frequency Distribution of ABO and Rh(D) Blood Groups in Goa

Background: The ABO and Rh(D) blood group systems are critical for transfusion safety and population genetics. Despite extensive studies in India, Goa's blood group distribution remains under-researched, with only one prior district-level study. This study aims to determine the phenotype, allele, and genotype frequencies of ABO and Rh(D) blood groups across Goa and compare them with regional and global data.Methods: A retrospective analysis of 16,417 blood samples (2015–2024) from Suburban Diagnostics Goa was conducted. ABO/Rh(D) typing used hem-agglutination, with allele/genotype frequencies calculated via Hardy-Weinberg equilibrium. Statistical comparisons employed chi-square tests. Result: Phenotype frequencies were O (32.68%) > A (32.28%) > B (26.34%) > AB (8.69%); Rh(D)+ prevalence was 94.11%. Allele frequencies were calculated to be IO (57.17%), IA (23.43%), and IB (19.66%); Rh(D) alleles were ID (75.73%) and Id (24.27%). When compared with aggregated data from Western India, statistically significant proportional differences were observed.Conclusion: Goa shows an ABO and Rh(D) blood group distribution with the order O > A > B > AB, differing from patterns seen in other regions of India. This variation may be influenced by historical genetic admixture. These findings are important for strengthening blood bank management and ensuring safe and efficient transfusion services in Goa.