Phenotype Frequencies of P1 Blood Group Antigen among Residents in Calabar, Nigeria

Abstract

Introduction: The P1 blood group antigen is part of a clinically relevant blood group system that plays an important role in blood transfusion. The prevalence of the P1 blood group antigen among individuals in Calabar, Cross River State, Nigeria, is not yet known. Aims: This study determined the phenotype frequency of P1 antigen among residents of Calabar metropolis and described its distribution by ABO/Rh blood group, gender and ethnicity. Materials and Methods: A cross-sectional study design was employed, and a total of 100 individuals who provided informed consent were enrolled. Fifty-nine (59) participants were males and forty-one (41) were females. The P1 blood group was analysed using the standard serological tube technique with Lorne reagent purchased from Lorne Laboratory, Great Britain, United Kingdom. Results: The frequency of P1 antigen in this study was 71 (71.0%). The distribution of ABO/Rh blood groups among the participants was as follows: O Rh 'D' positive, 77 (77.0%); A Rh 'D' positive, 10 (10.0%); B Rh 'D' positive, 9 (9.0%); AB Rh 'D' positive, 1 (1.0%); A Rh 'D' negative, 1 (1.0%); and O Rh 'D' negative, 2 (2.0%). The most prevalent ethnic group was Efik, 46 (46.0%), followed by Igbo, 18 (18.0%); Ijaw, 10 (10.0%); Ibibio, 10 (10.0%); Anang, 7 (7.0%); Oron, 4 (4.0%); Hausa, 3 (3.0%); and Yoruba, 2 (2.0%). Conclusion: A prevalence of 71.0% of P1 antigen was recorded among individuals in Calabar metropolis in this study. Although P1 antigen is a lesser-known blood group antigen and its complications are not as widely documented as those of major blood group systems, such as ABO and Rh, it may still influence transfusion reactions, immune responses and disease susceptibility.