A total of 95 patients with Graves’ disease (GD) and 105 normal healthy controls were enrolled in this study to determine how a single site polymorphism of the transporter associated with antigen processing 1 (TAP1) gene contributes to the pathogenesis of GD. The polymorphism was detected using polymerase chain reaction (PCR)-based restriction analysis. Associations between GD and the two-site polymorphisms of the TAP1 gene at codons 333 and 637 were evaluated. No significant differences were revealed comparing GD patients and normal individuals for the distributions of genotypes and allelic variants at codon 333 (p=0.253 and p=0.891, respectively). By contrast, the distributions for the AA homozygote at codon 637 were reduced and those for the GA heterozygote were increased comparing the two groups (p<0.0001). The allelic analysis also demonstrated lower A and higher G allele frequencies (p=0.0008; OR=2.745, 95% CI=1.482-5.085) comparing the GD patients with the normal healthy controls. This shows that the single-site polymorphism of the TAP1 gene at codon 637 may be an indicator for predicting development of GD.
