KMT2A and leukemia: The MLL-AF4 fusion protein, one of the most common rearrangements of the MLL (Mixed Lineage Leukemia) gene that promotes leukemogenesis, regulates promoter-enhancer interaction between PROM1 and its nearby gene TAPT1 by recruitment of DOT1L (Dot1-like, histone H3K79 methyltransferase) and subsequent increase of histone H3K79me2/3 on intragenic enhancer elements present in both genes, which in turn potentiate transcription of PROM1 and TAPT1 genes in some MLLr leukemias [58].