DYNC1H1 and proximal spinal muscular atrophy: Indeed, mutations in the cytoplasmic dynein 1 heavy chain (DYNC1H1)-encoding gene have been implicated in neurological disorders such as spinal muscular atrophy, lower extremity, dominant (SMA-LED)22, Charcot–Marie–Tooth disease, axonal, type 2 O (CMT2O)23, and malformations of cortical development (MCD)24.