부산대학교 도서관

OBJECTIVE: To determine the role of cytotoxic T lymphocyte associated antigen 4 (CTLA-4) genetic polymorphisms in susceptibility to systemic sclerosis (SSc, scleroderma). METHODS: The study population consisted of 293 African American and Caucasian patients with SSc and matched controls. Subjects were genotyped for allelic determinants at 4 polymorphic sites: 3 in the promoter region (positions –318, –1661, –1722) and one in the first exon (position +49) of the CTLA-4 gene, using polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) methods. Genotype frequencies were compared using Pearson's chi-square or Fisher's exact test. RESULTS: In African American patients, the frequency of AG heterozygotes at position +49 was significantly higher than in controls (71% vs 36%, p = 0.003; OR = 4.37), while the frequency of AA homozygotes was significantly lower in patients than in controls (29% vs 61%, p = 0.007; OR = 0.26). The distribution of CTLA-4 alleles at other loci did not differ significantly between patients and controls. CTLA-4 genotypes were not associated with SSc in Caucasians. No differences in CTLA-4 genotype distributions were observed between patients with the limited and diffuse forms of the disease. CONCLUSION: Our data show that the exon 1 (+49) polymorphism of the CTLA-4 gene is associated with systemic sclerosis in African Americans.