Deletions of cell cycle regulatory genes CDKN2A/CDKN2B are not frequent in DIPG, but the dysregulation of the cell cycle checkpoint has been reported in about 25–30% of DIPG, with the amplification of CCND2 and deletions of CDKN2C predominating ones [21]. The gene discussed is CDKN2A; the disease is diffuse intrinsic pontine glioma.