It is worth noting that POT1 mutations drive carcinogenesis in melanoma, glioma and CLL patients usually in combination with an array of other defective genes, such as CDKN2A, CDK4, BAP1, Notch1, SF3B1, TP53 and ATM, which have already been identified to predispose patients to these malignant diseases. The gene discussed is ATM; the disease is central nervous system cancer.