[Genetic predisposition to multiple sclerosis as a polygenic autoimmune disease].

Unrelated patients with definite multiple sclerosis (MS) and healthy controls of Russian descent were genotyped at 16 polymorphic loci of the DRB1, TNF, LTa, TGFb1, CCR5 and CTLA4 genes and TNFa and TNFb microsatellites. The association of allelic variants with MS (p<0,01) was studied using the case-control method with the PSampler algorithm recently developed by our group. The previously described DRB1*15(2) allele, the TNFa9 allele and the biallelic combination (CCR5d32,DRB1*04) were reidentified as MS-associated in Russians.

Three allele combinations associated with multiple sclerosis.

Background: Multiple sclerosis (MS) is an immune-mediated disease of polygenic etiology. Dissection of its genetic background is a complex problem, because of the combinatorial possibilities of gene-gene interactions. As genotyping methods improve throughput, approaches that can explore multigene interactions appropriately should lead to improved understanding of MS.

[Polymorphism of length of tetranucleotide repeat from the 5'-side from the myelin basic protein gene in multiple sclerosis in Russians].

The myelin basic protein gene (MBP) can confer the susceptibility to multiple sclerosis, because its protein product is the main protein component of myelin of the central nervous system and a potential autoimmune antigen in the disease. A possible association of multiple sclerosis with alleles and genotypes of a microsatellite repeat (TGGA)n, located to the 5' side from the first exon of MBP in ethnic Russians (126 patients with reliable multiple sclerosis and 142 healthy controls from Central Russia) was analyzed using the case-control method. Upon separation of the tetranucleotide repeat site amplification products in 1.

Myelin basic protein gene is associated with MS in DR4- and DR5-positive Italians and Russians.

Background: The myelin basic protein (MBP) gene may confer genetic susceptibility to multiple sclerosis (MS). The association of MS with alleles of the (TGGA)n variable number tandem repeat (VNTR) 5' to the MBP gene is the subject of conflicting reports.

Objective: To study possible MS association with VNTR alleles of MBP gene in ethnic Italians and ethnic Russians.

The chemokine receptor CCR5 deletion mutation is associated with MS in HLA-DR4-positive Russians.

The authors studied the possible association between the presence of a 32-base pair deletion allele in CC chemokine receptor 5 gene [3p21] (CCR5 Delta 32 allele) and the occurrence of MS. The presence of CCR5 Delta 32 homozygotes among patients with MS indicates that the absence of CCR5 did not protect against MS. Moreover, the CCR5 Delta 32 mutation was associated with MS in HLA-DR4-positive Russians (p(corr) < 0.

[Polymorphism A/G in position +49 of CTLA4 exon 1 in multiple sclerosis in Russians].

The association of multiple sclerosis (MS) with alleles A and G of the cytotoxic T-lymphocyte antigen 4 (CTLA4) gene, a candidate gene for autoimmune disorders, was studied. The allele polymorphism results from single nucleotide substitution (A/G) in position +49 of exon 1 and leads to substitution Thr-->Ala in the leader peptide. The case-control study involved two groups of ethnic Russians: 168 MS patients and 209 healthy subjects from central Russia.

Association and linkage of juvenile MS with HLA-DR2(15) in Russians.

The aim of this study was to determine the role of the HLA-DRB1 gene [6p21] in susceptibility to juvenile MS (JMS) (age at onset < or =15 years) of children of Russian descent. Association of DR2(15) with JMS has been found by the comparison of patients with JMS with both unrelated and affected family-based healthy controls. The linkage of DR2(15) with JMS was shown by transmission disequilibrium test.