We previously showed that G34V/R-H3.3 GBM samples universally also carried ATRX and TP53 mutations (13/13), while K27M-H3.3 GBM samples had significant, albeit lower, overlap with ATRX and TP53 mutations (respectively, 30 and 60 % of the 10 samples investigated) [23]. Here, ATRX is linked to glioblastoma.