Correlations between FTO Gene Polymorphisms and TSH Level in Uyghur Chinese Patients with Type 2 Diabetes

Abstract

Objective. The aim of this study was to investigate the correlation between polymorphisms in the FTO gene and TSH level in Uyghur patients with type 2 diabetes in the Xinjiang region. Material and Methods. This cohort was made up of 498 Uyghur patients with type 2 diabetes who underwent genotype screening for rs8050136 and rs9939609 using the Sequenom MassARRAY system. The distribution frequencies of the genotypes and alleles at rs8050136 and rs993960 were compared between two patient groups, those with $\text{TSH}<2.5$  mU/L and those with $\text{TSH}\ge 2.5$  mU/L group. We further evaluated the relationships between these different genotypes and FT3, FT4, TSH, FPG, and HbA1c expression. Results. The results suggested the TSH level was 2.281 times higher in rs8050136 CC+CA carriers than in AA genotype ( $95\%\text{CI}=1.024$ ~5.080, $P=0.044$ ) and was 2.417 times higher in rs9939609 TT+TA carriers than in AA genotype ( $95\%\text{CI}=1.257$ ~4.649, $P=0.008$ ) after adjusting for age, sex, and BMI under the recessive model. TSH levels were significantly different between T2DM patients with different FTO genotypes, rs8050136 ( $P=0.008$ ) and rs9939609 ( $P=0.003$ ), with TSH levels in rs8050136 CC genotype carriers showing a significant increase compared to those in the AA genotype carriers ( $P=0.005$ ). Additionally, rs9939609 TT and TA genotype carriers had a significant increase in the TSH level when compared to AA genotype carriers ( $P=0.001$ and $P=0.031$ , respectively). The TSH level was also significantly different in these male patients with different genotypes of rs8050136 ( $P=0.026$ ) and rs9939609 ( $P=0.019$ ). And TSH levels in rs8050136 CC genotype male carriers showing a significant increase compared to those in the AA genotype carriers ( $P=0.013$ ) and rs9939609 TT genotype male carriers had a significant increase in TSH level when compared to AA genotype carriers ( $P=0.004$ ). Conclusion. The polymorphisms at rs8050136 and rs9939609 are associated with changes in the TSH level with rs8050136 CC and rs9939609 TT genotypes identified as potential risk factors for increased TSH levels in these male patients.