Distinct HLA Class I and II Genotypes and Haplotypes Are Associated with Multiple Sclerosis in Bahrain

Multiple sclerosis (MS) has become prevalent in the Arabian Gulf area with high incidence in Bahrain due to environmental influences and genetic susceptibilities, but there is a lack of study into human leukocyte antigen (HLA) types in patients with MS in Bahrain. The present study aimed to study the HLA types expressed in MS patients compared with in control subjects. Blood samples from 50 Bahraini patients with MS and 50 Bahraini control subjects' were subjected to HLA tissue typing by polymerase chain reaction using sequence-specific primers. In comparison with those in control subjects, the allele frequencies of HLA class-I antigens A2, A9, A19, B5, B35 and B40 were higher in MS patients. For class II antigens, the allele frequencies of DR3, DR4 and DR16 were higher in MS patients. The allele frequency of DR15 was lower in MS patients than in control subjects but the difference was not statistically significant (P=0.138). The higher prevalence of the HLA-ABDR allele was common among the female patients with MS, in relapse remission stage, in cases with higher expanded disability status scale scores and with disease duration between 4 and 9 years. Haplotype HLA-A2-B40-DR2 exhibited significantly higher frequency in MS patients compared with in control subjects (P=0.03). In conclusion, the results indicated different alleles associated with MS compared with previous reviews. The present study supports the importance of identifying genetic susceptibilities and targets for therapies in specific populations and individuals, to personalize disease management in terms of prediction, protective measures and treatment.