Specifically, H3K4 methyltransferase Mixed-lineage leukemia 4 (Mll4) in mice, also known as Lysine Methyltransferase 2D (KMT2D) in human, regulates neuronal differentiation and tumor suppression, and its loss triggers G3-like MB development with upregulating oncogenic Ras and Notch pathways, and downregulating tumor suppressor genes (e.g., Dnmt3a, Bcl6) (61) (Figure 3b). The gene discussed is KMT2D; the disease is neoplasm.