Exon-1 polymorphism of ctla-4 gene in Iranian patients with Graves' disease.

Polymorphisms in ctla-4 gene have been shown to be associated with the Graves' disease (GD) susceptibility in different populations in the world. This study was undertaken to disclose the probable association of exon-1 polymorphism of ctla-4 with GD in Iranian patients. A49G polymorphism was investigated in 90 patients and 90 age/sex matched normal healthy controls, using PCR-SSCP and PCR-RFLP methods. Frequencies of AA, AG and GG genotypes among patients were found to be 21 (23.3%), 49 (54.5%) and 20 (22.2%) while these frequencies among healthy controls were 30 (33.3%), 53 (58.9%) and 7(7.8%), respectively. A significant increase of GG genotype and G allele was observed in patients (p = 0.012 and p = 0.025). In conclusion, consistent with the results of most other studies, the presence of a G allele in position 49 of ctla-4 exon-1 is associated with susceptibility to GD in Iranian population.