Monarch Disease Ontology identifier MONDO_0014993 (myofibrillar myopathy 8) is any myofibrillar myopathy in which the cause of the disease is a mutation in the PYROXD1 gene. Also known as: PYROXD1 myofibrillar myopathy (disease), myofibrillar myopathy (disease) caused by mutation in PYROXD1, myopathy, myofibrillar, 8, myopathy, myofibrillar, type 8.