The CTLA-4 gene is associated with multiple sclerosis

We have investigated whether three intragenic polymorphisms of the CTLA-4 g ene, a C/T base exchange in the promoter (p. - 318), an A/G substitution in exon 1 (p.49) and a dinucleotide repeat polymorphism in exon 4 (p. 642), w ere associated with genetic susceptibility to multiple sclerosis (MS). We o bserved a significant association (p < 0.05) for homozygosity for the G(49) allele in a case-control analysis of 378 MS patients and 237 controls, and a transmission disequilibrium (p < 0.02) for the G(49) allele in 31 MS fam ilies. This was further corroborated by evidence for linkage by the affecte d pedigree member (APM) analysis (p < 0.0002) and a transmission distortion (p < 0.05) of the exon 4(642) polymorphism. Sequencing of the promoter, th e first and second exons and the parts of the first intron revealed no furt her polymorphisms. Our results suggest that a dysregulation of CTLA-4-drive n downregulntion of T-cell activation could be involved in the pathogenesis of MS. (C) 1999 Elsevier Science B.V. All rights reserved.