GNE myopathy is a slowly progressive muscle disease that typically presents between age 20 and 40 years with bilateral foot drop caused by anterior tibialis weakness. Lower-extremity muscle involvement progresses from the anterior to the posterior compartment of the lower leg, followed by hamstrings, then hip girdle muscles, with relative sparing of the quadriceps. A wheelchair may be needed about ten to 20 years after the onset of manifestations. The upper extremities, which may be affected within five to ten years of disease onset, do not necessarily follow a distal-to-proximal progression. In advanced stages, neck and core muscles can become affected.

An autosomal recessive condition caused by mutation(s) in the GNE gene, encoding bifunctional UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase. It is characterized by distal muscle weakness and atrophy, especially the tibialis anterior, and sparing of the quadriceps.

Inclusion body myopathy 2, also known as hereditary inclusion body myopathy (HIBM), GNE -related myopathy, distal myopathy with rimmed vacuoles, and Nonaka myopathy, is an inherited condition that primarily affects the skeletal muscles (the muscles that the body uses to move). This disorder is characterized by muscle weakness that...