The aims of the present study were (1) to determine serum resistin, IGF-1, TSH, fT4, lipid, and transaminase levels together in untreated patients with hyper-and hypothyroidism and control groups for the first time and (2) to investigate potential relationship between thyroid function and serum levels of resistin and IGF-1 in HT and HrT patients. The gene discussed is IGF1; the disease is hematocrit.