| Abstract: | Background and objective: The HLA‐DRB1*15 allele is consistently associated with multiple sclerosis (MS) susceptibility in most studied populations. This study investigated the association between HLA‐DRB1 alleles and the presence of oligoclonal immunoglobulin G bands (OCB) in the cerebrospinal fluid (CSF) in a Spanish population with MS. Methods: The HLA‐DRB1 typing was performed in 268 patients with sporadic MS and the detection of OCB in CSF. HLA‐DRB1 allelic frequencies were compared between OCB‐positive and OCB‐negative patients, and both groups were also compared with 1088 unrelated healthy controls. Moreover, we correlated the various HLA‐DRB1 genotypes, considering all the combinations of both parental alleles found with the presence or absence of OCB. Results: We found 206 OCB‐positive and 62 OCB‐negative patients. The HLA‐DRB1*15 allele in OCB‐positive patients had a higher frequency when compared with OCB‐negative patients (39.3% in OCB‐positive vs. 16.1% in OCB‐negative, OR = 1.38 95% CI = 1.18–1.61, P < 0.001). The other alleles did not show differences. When we compared with controls, the HLA‐DRB1*15 allele was associated with the disease only in the OCB‐positive patients group. None of the 55 genotypes found showed any association with the presence or absence of OCB. Conclusions: HLA‐DRB1*15 allele is associated with OCB‐positive patients with MS when studying a Spanish MS population. |
