atrial fibrillation, familial, 13 (MONDO_0014155, a Monarch Disease Ontology entry) is any familial atrial fibrillation in which the cause of the disease is a mutation in the SCN1B gene. Also known as: SCN1B familial atrial fibrillation, atrial fibrillation, familial, type 13, familial atrial fibrillation caused by mutation in SCN1B.