Diagnostic value of CNV in CYP1A2, CYP2A6, CYP2C19, CYP2C9, CYP2D6, CYP2E1, CYP3A4, CYP3A5, GSTM1, GSTP1 and GSTT1 for prediction of optimal response and failure of TKI therapy in CML patients (P = 0.0001). This evidence concerns the gene CYP2C9 and chronic myelogenous leukemia, BCR-ABL1 positive.