KMT2A and leukemia: Several fusion proteins are described in acute leukemia, mainly with other epigenetic or transcriptional regulators like AFF1, MLLT1, or MLLT3, accounting for strongly divergent epigenomic, and gene expression patterns in KMT2A‐rearranged (KMT2A‐r) leukemia compared to other cytogenetic entities [25, 26].