Spinal Muscular Atrophy, Lower Extremity-Predominant, 2a, Childhood Onset, Autosomal Dominant, also known as smaled2a, is related to spinal muscular atrophy with lower extremity predominant and spinal muscular atrophy with lower extremity predominant 2a. An important gene associated with Spinal Muscular Atrophy, Lower Extremity-Predominant, 2a, Childhood Onset, Autosomal Dominant is BICD2 (BICD Cargo Adaptor 2). Affiliated tissues include spinal cord and skeletal muscle.