nephronophthisis 20 (Monarch Disease Ontology term MONDO_0014997) can be described as follows. Any nephronophthisis in which the cause of the disease is a mutation in the MAPKBP1 gene. Also known as: MAPKBP1 nephronophthisis (disease), NPHP20, nephronophthisis (disease) caused by mutation in MAPKBP1, nephronophthisis type 20.