However, PBMC of de novo CP-CML patients and BP-CML patients demonstrated no expression of p-ATM and predominantly no expression of p-CHK2 (apart from strong expression of p-CHK2 in BP-CML#2), which was in contrast to the presence of relatively high levels of DNA damage in these cells as evidenced by γH2AX foci analysis. The gene discussed is ATM; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.