Compared to the control group, male CS patients showed significant lower levels of HCT (median 42.9 vs 44.7%, p = 0.027), RBC count (4.8 vs 5.1 n*106/μl, p = 0.001), Hb (14.2 vs 15.4 g/dl, p = 0.001), and MCHC (33.6 vs 34.6 g/dl, p < 0.0001), but higher levels of MCV (90.8 vs 87.5 fl, p < 0.0001) and MCH (31.1 vs 30.0, p = 0.020 pg) (Table 2). Here, GSTM1 is linked to Cowden syndrome 1.