the influence of combined genotypes of the hladrb1*1501 and cd24 single nucleotide polymorphism on disease severity of iranian multiple sclerosis patients.

multiple sclerosis (ms) is an inflammatory demyelinating disease of the central nervous system. it is a clinically heterogeneous disorder especially in terms of disease severity. current investigations suggest that genes and gene-gene interactions not only influence on susceptibility to ms but also affect the disease severity. in this study, we investigated the contribution of the hladrb1*1501 allele and single nucleotide polymorphism (snp) in cd24 gene and also combined genotypes of the hladrb1*1501 and cd24 snp to disease severity in iranian ms patients. we have reported previously that the hla- drb1*1501 allele and the cd24v/v genotype associated with disease susceptibility and some other studies proposed that hla-drb1*1501 allele be associated with ms severity. in this study, the results showed a significant difference in the multiple sclerosis severity score (msss) of the nine different genotypes (f=2.838, p=0.007). subsequent analysis revealed a statistically significant difference in the msss between the ms patients who were carriers of hla-drb1*1501/1501 and those who were not carriers of hla-drb1*1501/1501 genotypes (p=0.04). moreover, the ms patients carrying combined genotypes of the hla- drb1*1501/x-cd24 v/v had statistically severe disease than the patients who did not carry the hla- drb1*1501- cd24 v/v (p=0.047). in conclusion, our findings suggest that, hla-drb1*1501/1501 and bigenic genotypes of the hla- drb1*1501/x- cd24 v/v may influence on disease severity in iranian ms patients.