Multiple sclerosis: Association to HLA DQ alpha in a tropical population

Studies performed in subtropical populations have found significant associa tion between the phenotype multiple sclerosis (MS) and the major histocompa tibility complex (MHC). We present the results of a case-control study cond ucted on a tropical population (Antioquia, Colombia) in order to detect a p ossible association between MS and HLA DQ alpha (HLA DQA1*) alleles. Forty chromosomes belonging to MS patients were compared to two sets of controls (40 and 910 chromosomes, respectively). The HLA DQA1*0101 and DQA1*0102 all eles were found in a significantly higher proportion among the cases than a mong the controls, whereas the HLA DQA1*0103 allele was found in a signific antly lower proportion of the cases. These results suggest that the associa tion of HLA DQA1*0101, DQA1*0102 and DQA1*0103 to the MS phenotype found in Caucasian subtropical populations remains in individuals with MS inhabitin g the tropics. This finding could mean that the major genetic component ass ociated to the MHC in subtropical populations is the same in the tropics.