In patients with distal spinal muscular atrophy (or SMALED), in fact, there is the prevalent involvement of thigh muscles with sparing or hypertrophy of adductor longus and tibialis anterior (i.e. DYNC1H1 mutated patients) or of biceps femorii and medial gastrocnemius (i.e. TRPV4 mutated patients) [36] differently from those described in MYH-7 related myopathies. This evidence concerns the gene DYNC1H1 and distal hereditary motor neuropathy.