ATRX has been observed to be frequently mutated (typically in at least 80% of patients in case series but up to 100% in some) in H3.3-G34R/V mutant gliomas [50,51,52,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85]. The gene discussed is ATRX; the disease is central nervous system cancer.