The significance of rare genetic alterations, such B-cell lymphoma-6 corepressor (BCOR) and B-cell lymphoma-6 corepressor-like protein 1 (BCORL1) mutations, in pediatric acute myeloid leukemias (AML) and myelodysplastic syndrome (MDS) is unknown. Here, BCORL1 is linked to acute myeloid leukemia.