Bicd2-Related Autosomal Dominant Childhood-Onset Proximal Spinal Muscular Atroph, also known as bicd2-related lower extremity-predominant autosomal dominant proximal spinal muscular atrophy with contractures, is related to contractures, pterygia, and spondylocarpotarsal fusion syndrome 1a and spinal muscular atrophy. An important gene associated with Bicd2-Related Autosomal Dominant Childhood-Onset Proximal Spinal Muscular Atroph is BICD2 (BICD Cargo Adaptor 2). Affiliated tissues include brain, and related phenotypes are waddling gait and difficulty walking