Human leukocyte antigen (HLA) molecules appear on the surface of antigen-presenting cells and are essential for adaptive immune function. Within class I genes, several HLA-B variants have been linked to adverse drug reactions (ADRs) and are applied as pharmacogenetic indicators. Although ADRs contribute substantially to hospital admissions and deaths, information describing the distribution of HLA-B pharmacogenetic markers across Arab populations remains limited. In this work, we assessed the occurrence of key HLA-B pharmacogenomic markers in individuals from Qatar. High-throughput sequencing data from 1,098 Qatari participants were analyzed for HLA-B genotyping using HLA-HD version 1.4.0 and the IPD-IMGT/HLA reference database. Pharmacogenetic HLA-B markers were additionally retrieved from the HLA Adverse Drug Reaction Database. Altogether, 469 principal HLA-B markers relevant to pharmacogenetics were detected. HLA-B51:01 showed the highest frequency (26.67%) in the Qatari cohort and is linked to ADRs caused by phenytoin and clindamycin. The next most common allele was HLA-B58:01 (6.56%), associated with allopurinol-related reactions. HLA-B*44:03 ranked third and is tied to phenytoin-induced hypersensitivity. The presence of these prevalent HLA-B markers supports the value of implementing a pharmacogenetic screening strategy in Qatar to reduce drug-related hypersensitivity events in a cost-effective manner.
