 Type 2 (DM2), also known as proximal myotonic myopathy (PROMM), is rarer and generally manifests with milder signs and symptoms than DM1.Other forms of myotonic dystrophy not associated with DM1 or DM2 genetic mutations have been described.One case which was proposed as a candidate for the "DM3" label, was later characterized as an unusual form of inclusion body myopathy associated with Paget's disease and frontotemporal dementia.