Allele frequencies of Human Platelet Antigen 1 and Human Platelet Antigen 5 in the Maltese

Abstract

Background: The human platelet antigen systems consist of antigenic polymorphisms that arise from single base pair substitutions leading to amino acid changes in platelet glycoproteins. These polymorphisms cause a variety of clinically significant conditions where platelet typing is essential for accurate diagnosis and subsequent treatment. The aim of this study was to determine the allele frequencies of Human Platelet Antigen-1 (HPA-1) and Human Platelet Antigen-5 (HPA-5) in the Maltese population and to compare these frequencies to those in other populations.

Methods: This study was conducted on a total of 508 population DNA samples. Polymerase chain reaction was used to amplify segments of DNA spanning the single nucleotide polymorphism of interest for both the HPA-1 and HPA-5 systems. A restriction enzyme digest was then used to differentiate between the genotypes. The data was analysed by gender and nationality.

Results and Conclusion: From this study it was determined that, for these two polymorphisms, the Maltese population is in Hardy-Weinberg equilibrium and that the local allele frequencies are similar to frequencies of geographically close populations. The frequencies of these two HPA systems are: HPA-1a/1a; 71.6%, HPA-1a/1b; 25.5%, HPA-1b/1b; 2.9%, HPA-5a/5a; 77.4%, HPA-5a/5b; 22.0% and HPA-5b/5b; 0.6%.