GPT and primitive neuroectodermal tumor: Using two methods for detecting C-Circles (dot blot relative intensity, see Table S6, and telomeric qPCR) allowed us to identify seven cases, positive to both tests for ALT including, two CNS-PNET, 1 ODG, one juvenile GBM and three GBM/PNC (see Table 1 and black dots in Figure 4a).