Mondo Description Nonaka distal myopathy (described in Japan) and the quadriceps-sparing autosomal recessive inclusion body myopathy type 2 (IBM2; independently described in Iranian Jews and later in other Jewish and non-Jewish populations) constitute the same pathological entity, distinguished by the sparing of quadriceps.

Uniprot Description Autosomal recessive muscular disorder, allelic to inclusion body myopathy 2. It is characterized by weakness of the anterior compartment of the lower limbs with onset in early adulthood, and sparing of the quadriceps muscles. As the inclusion body myopathy, NM is histologically characterized by the presence of numerous rimmed vacuoles without inflammatory changes in muscle specimens.