Objective: 

Thyroid hormones have an important role on normal growing and developing of skeletal muscle. Insulin like growth factor-I (IGF-I) is important growing factors and it is necessary for produced and developing of thyroid cells. IGF-I stimulates fibroblast, follicular cells and endothelial cells in thyroid glands. It was shown that thyroids hormones have an important role on regulation of IGF-I and insulin like growth factor binding protein-3 (IGFBP-3). In present study, we investigated the frequencies of IGF-I (CA)19 and IGFBP-3 -202 A/C gene polymorphisms in thyroid diseases with hyperthyroid or hypothyroid states and it may be the role of this polymorphisms in thyroid functions.

Methods: 

This study was performed of thirty-seven patients with hyperthyroidism, seventy-six patients with hypothyroidism and fifty healthy controls. Genomic DNA from the patients and controls was prepared from peripheral blood samples. Investigated genomic areas were studied using specific primers by PCR methods. Amplified fragments were separated agarose gel electrophoresis and identified using the UV gel documentation system.

Results: 

The frequencies of IGF-I (CA)19 gene polymorphism were found statistically significant among the patients with hypothyroids, hyperthyroids and healthy controls. Although we did not find any difference between control and patient groups compared to the frequency of IGF-I (CA)19 gene polymorphism, the difference of genotypes between patients with hypothyroids and hyperthyroids was statistically significant. The frequency of IGFBP3 -202 A/C gene polymorphism was found statistically significant between hypothyroid and hyperthyroid patients, x2=6.24 df=2 p=0.044.

Conclusions: 

In conclusion, IGF-I (CA)19 and IGFBP-3 -202 A/C gene polymorphisms may be a risk factor for hypothyroidism. This study was supported by Pamukkale University Research Fund.