Associations of gene polymorphisms in interferon-alpha signature-related genes with autoimmune thyroid diseases.

UNLABELLED: Interferon (IFN)-α treatment predisposes patients to the occurrence of autoimmune thyroid disease (AITD).

METHODS

We investigated associations of single nucleotide polymorphisms (SNPs) of molecules participating in the IFN-α signature, including rs2304204 and rs2304206 of IFN regulatory factor 3 (IRF3), rs1061501 of IRF7, and rs7708392 of TNFA1P3-interacting protein 1 with serum IFN-α levels and AITD in an ethnic Chinese (ie Taiwanese) population. Totally, 319 patients with Graves' disease (GD), 83 patients with Hashimoto's thyroiditis (HT) and 351 healthy controls were recruited.

RESULTS

There were increased percentages of the C allele, and CC and TC + CC genotypes of rs1061501 in GD patients compared to the controls. HT patients had higher serum IFN-α levels compared to the controls, while there was no difference in serum IFN-α levels between patients with GD and controls. However, patients with GD in a remission status had lower serum IFN-α levels than those without remission. On the other hand, the C allele of rs1061501 was only associated with serum IFN-α levels in patients with HT.

CONCLUSIONS

The SNP rs1061501 of IRF7 was associated with the development of GD. Serum IFN-α levels were associated with HT, while they might modify the disease status of GD. Moreover, a genetic effect of rs1061501 on regulating serum IFN-α production was observed in HT.