The ASXL1 (ASXL Transcriptional Regulator 1) gene is a protein-coding gene located on chromosome 20q11.21.. The encoded protein belongs to the group of so-called Polycomb proteins. These are involved in transcriptional regulation mediated by ligand-gated nuclear hormone receptors such as retinoic acid receptors (RARs) and peroxisome proliferator-activated receptor gamma (PPARG). The protein is thought to affect chromatin in specific areas, promoting transcription of certain genes while repressing transcription of others.
Mutations in this gene are associated with myelodysplastic syndromes and chronic myelomonocytic leukemia.
Diseases associated with ASXL1 include Bohring-Opitz syndrome. Related pathways include CDK-mediated phosphorylation and removal of Cdc6 and deubiquitination. An important paralog of this gene is ASXL3.