The association between rs4684677 T/A polymorphism in preproghrelin gene and predisposition to autoimmune thyroid diseases in children.

BACKGROUND

A potential role of preproghrelin polymorphisms on autoimmune thyroid diseases (AITDs) has not been established equivocally yet.

AIM: To estimate the association of two polymorphisms of preproghrelin gene with the predisposition to Graves' disease (GD) and Hashimoto's thyroiditis (HT) in children.

METHODS

The study was performed in 145 patients with GD, 87 with HT and 161 healthy volunteers. The two single nucleotide polymorphisms (SNPs) rs696217 (C_3151003_20) and rs4684677 (C_25607748_10) in the preproghrelin gene were genotyped by TaqMan SNP genotyping assay using the real-time PCR.

RESULTS

Rs4684677 T alleles were more frequent in HT patients (99% in women and 100% in men) in comparison to healthy subjects (p = 0.002) with OR = 8.0 and 95% confidence interval for OR: 1.8-206.7. In women group, rs4684677 T alleles were more frequent compared to healthy controls (99%) in HT (p = 0.02) with OR = 6.7 and 95% confidence interval for OR: 1.2-168.37. Frequency of the SNP rs696217 did not differ between the groups. There was a significant relationship between rs696217 polymorphisms and anti-TSHR antibodies level (p = 0.036) in women from GD/HT groups. A significant relationship between rs696217 polymorphisms and anti-TG antibodies level in GD women group (p = 0.038) and between rs696217 polymorphisms and fT4 concentration (p = 0.03) were found.

CONCLUSIONS

Rs4684677 T/A polymorphisms in preproghrelin gene could contribute to development of AITDs in children and T allele is the main risk factor.