HLA class II polymorphism in Latin American patients with multiple sclerosis

Objective To identify HLA-DRB1 alleles contributing to susceptibility to multiple sclerosis (MS) in a Colombian population and to estimate the common effect size of HLA class II on MS susceptibility in Latin American populations through a meta-analysis. Methods A total of 65 Colombian patients with MS and 184 matched controls were included. HLA-DRB1 typing was done using the sequence-specific oligonucleotide probe method. A bivariate and a multivariate logistic regression analyses were done. Case-control studies performed in Latin America were searched up to January 2009 through a systematic review of the literature. Effect summary odds ratios (ORs) and 95% confidence intervals (CIs) were obtained by means of the random effect model. Results A total of 464 cases and 2581 controls from 7 studies and the results of the present study in Colombians were analyzed. HLA-DRB1 15 (OR: 2.3; 95% CI: 1.68–3.07; p < 0.001) and HLA-DQB1 06 (OR: 2.2; 95% CI: 1.54–3.07; p < 0.001) groups as well as DRB1 1501 (OR: 2.6; 95% CI: 1.67–4.02; p < 0.001), DRB1 1503 (OR: 2.2; 95% CI: 1.39–3.62; p = 0.001) and DQB1 0602 (OR: 2.5; 95% CI: 1.66–3.71; p < 0.001) alleles were found to be risk factors for MS. The myelin basic protein immunodominant sequence 221VHFFKNIVT229 was predicted to strongly and simultaneously bind to HLA-DRB1 1501 and 1503. Conclusion The current study highlights the effect size of HLA class II in MS in Latin America and confirms similar allelic risk factors across diverse populations. Receptor-ligand interactions in the HLA-antigenic peptide complex could have potential predictive and therapeutical implications.