Serum DKK1 concentrations were significantly higher in females than in males in total sample (697±434 vs 563±293 pg/ml, P = 0,046) and in T2DM group (788±493 vs 569±255 pg/ml, P = 0,025) but were not significantly increased in control females (593±335 vs 553±349 pg/ml, P = 0,682). The gene discussed is DKK1; the disease is type 2 diabetes mellitus.