The aim of this study is to investigate the significance of the polymorphisms of the cytotoxic T lymphocyte associated antigen-4 (CTLA-4) exon 1(+49) and promoter(-318) genes in rheumatoid arthritis (RA). Polymerase chain reaction of genomic DNA-restriction fragment length polymorphism was used to determine genotypes of the CTLA-4 exon 1(+49) and promoter(-318) in 86 RA patients and 86 healthy control subjects. There was no significant difference in genotype, allele and phenotype frequencies of the CTLA-4 exon 1(+49) and promoter(-318) genes between RA patients and control subjects. There was no significant difference in age at onset, severity, functional class (> or = 3), physician global assessment, ESR, CRP or RF titer in patients with RA according to the CTLA-4 polymorphisms. Our data show that the polymorphisms within the CTLA-4 exon 1(+49) and promoter(-318) genes are not associated with susceptibility to RA and its clinical/serological manifestations in the Korean population.