Multiple sclerosis in Northern-West region of Russia:: results of HLA-typing

Distribution of antigens of A, B, DR loci of HLA system in standard lymphocytotoxic test was studied in 59 patients with a significant diagnosis of multiple sclerosis (MS) and in 138 healthy donors. In the patients elevated frequency of the next antigens was found as compared with the controls: A10 (37%; chi(2)=6,31; p<0,05; relative risk - RR=2,34), B7 (37%, chi(2)=4,62; p<0,05; RR=2,05), B13 (29%; chi(2)=10,86; p<0,01; RR=3,59), B35(17%; chi(2)=4,27; p<0,05; RR=2,61), DR2 (68%; chi(2)=11,61; p<0,001; RR=2,99), as well as DR6 (5%; chi(2)=3,95; p<0,05; RR=7,34) and also DRw52 (24%; chi(2)=27,49; p<0,001; RR=21,16), The highest value of etiologic fraction was found for DR2 antigen. Analysis of intralocus and extralocus combinations of antigens in MS revealed that significantly elevated frequency had only one combination - B7DR2 (25,4%; chi(2)=9,77; p<0,01; RR=3,58) relative risk was higher for this combination than for each individual antigen separately: B7 (RR=2,05), DR2 (RR=2,99), Significant negative associations with a possible protective effect of separate alleles were established in MS for antigens HLA A2 (34%; chi(2)=4,55; p <0,05; RR=0,47), A11 (7%; chi(2)=4,66; p<0,05;RR=0,31), A30 (0%; chi(2)=4,50, p<0,05; RR=0,01), B18 (8%; chi(2)=4,55; p<0,05; RR=0,35), DR5 (59%; chi(2)=10,17 p <0,01; RR=0,36). The most significant was a decrease of the frequency of DR5 antigen (p<0,01), Patients with the recurrent course had prevailed antigens A11, B21, B35 and decreased frequencies of antigens A9, B13, DR7. However, only the difference in the frequency of DR7 (16% in remitting and 57% in progredient course, chi(2)=10,02; p<0,001; RR=0,14) was significant.