Determining the genotype of the RH blood group system in the Maltese population

Abstract

Introduction: The Rh blood group system has a vital role in transfusion medicine therefore, by DNA typing important medical issues can be resolved when serological techniques are inconclusive. The main aim of this research was to determine the frequency of RHD and RHCE in the Maltese population so that in the future DNA typing can be employed to complement the routine serology techniques. Methods: 400 blood donor samples and 397 neonatal blood samples were enrolled in this study. An allele-specific polymerase chain reaction (AS-PCR) method was used to determine the presence of RHD, RHCE*E and RHCE*e, while multiplex PCR was used to test for RHCE*C/c. 81 from these 400 blood donor samples were tested by serology for the RhD, C,c,E and e antigens, and the results were used for comparison with the results obtained by genotyping. Results: Out of 797 samples, the most common allele was RHCE*e (98%), followed by RHD (91%). The lowest percentage was obtained for RHCE*E (23%). The most common haplotype in the study was DCe (49.7%). This is also expressed in the fact that DCcee and DCCee were the most common genotypes with a percentage of 38.27 and 24.46 respectively. In RHD negative samples, dccee was the most frequent (6.9%). Conclusion: Like in previous studies, this research also concludes that the distribution of the RH genotype varies in different geographical areas. The molecular techniques used, offer a fast in-house testing system to obtain the RHD and RHCE genotype status. However this may merit further development to be used in a clinical setting.