Multiple Sclerosis: Association to HLA DQα in a Tropical Population

Abstract

Studies performed in subtropical populations have found significant association between the phenotype multiple sclerosis (MS) and the major histocompatibility complex (MHC). We present the results of a case-control study conducted on a tropical population (Antioquia, Colombia) in order to detect a possible association between MS and HLA DQα (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 alleles were found in a significantly higher proportion among the cases than among the controls, whereas the HLA DQA1*0103 allele was found in a significantly lower proportion of the cases. These results suggest that the association of HLA DQA1*0101, DQA1*0102 and DQA1*0103 to the MS phenotype found in Caucasian subtropical populations remains in individuals with MS inhabiting the tropics. This finding could mean that the major genetic component associated to the MHC in subtropical populations is the same in the tropics.

Multiple Sclerosis in Latin America

“…In Colombia, MS prevalence shows geographic variations ranging from 1.48 to 4.98/100,000 [24] . Genetic studies in Medellin demonstrated in this population that HLA DQAI polymorphisms at chromosome 6p21.3-21.4 were associated with a high or low predisposition to suffer from MS [25,26] . Of interest, MS in this genetically homogeneous population presented clinically with a preponderance of optic neuritis and motor symptoms in the absence of cerebellar manifestations [27] .…”

HLA class II polymorphism in Latin American patients with multiple sclerosis

“…Despite the low prevalence of MS in Latin America, genetic studies in populations belonging to this geographical area offers a unique opportunity for examining the predisposition to develop MS because of the negative influence contributed by the admixture of Amerindians, Europeans and Negroids occurring 10-20 generations ago. This may resolve racial effects from genetic association with major genes [7]. The study of HLA as one of the major locus contributing to ADs will allow us to understand its common or specific influence on these diseases [2,8].…”

Campora: A Young Genetic Isolate in South Italy

“…The usefulness of isolated populations in these studies has been widely shown [3][4][5][6][7][8][9] . Isolated populations originate from a restricted number of founders due either to a past migration event or to a past reduction in the population size (e.g.…”