KDM5B and neoplasm: Jarid1b contributes to the myogenic, osteogenic and macrophage lineage specification of mesenchymal cells.8, 9, 10 Silencing of Jarid1b in ESCs impairs neural linage commitment.11 An RNAi screen identified Jarid1b as a major regulator of haematopoietic stem cell differentiation.12 Jarid1b contributes to trophoblast stem cell differentiation by downregulating self‐renewal genes via removing H3K4 methylation.13 Jarid1b has been reported to be highly expressed in various types of tumours.