Mutations in five telomere-related genes (the TERT promoter and the shelterin genes POT1, TPP1, TERF2IP, and TINF2) have been linked to the risk of familial melanoma, glioma, and chronic lymphocytic leukemia, and they explain 1–10% of families with these cancers and show autosomal dominant inheritance (see references in 66) (Figure 2; Table 1). Here, TERT is linked to glioma.