Interestingly, among tumors usually assumed to re-express the telomerase, 42% (8/19) of GBMs with ATRX alteration were indeed ALT + (2/7 was ATRXloss, 4/7 were also pTERTmt (regarding the VAF, 2 were subclonal TMM activation, 1 non available, 1 same ATRX-pTERT VAF) and 83% (6/7) of MAPK activated gliomas also exhibited ALT + status (4/5 with ATRXloss, all pTERTwt). The gene discussed is ATRX; the disease is central nervous system cancer.