Methods: Patients with AIS, at least two Cobb angle measurements in adolescence, and those with both low COMT (rs4680 AA) and low MTHFR (A1298C AC and C677T CT; A1298C AA and C677T TT) activity (Group 1) or those with intermediate or high COMT (rs4680 AG or GG) and MTHFR (A1298C AA and C677T CT; A1298C AC and C677T CC; A1298C AA and C677T CC) activity (Group 2) were included. This evidence concerns the gene COMT and androgen insensitivity syndrome.