Spastic Paraplegia 31, Autosomal Dominant, also known as spg31, is related to spastic paraplegia 3a and spastic paraplegia 3, autosomal dominant. An important gene associated with Spastic Paraplegia 31, Autosomal Dominant is REEP1 (Receptor Accessory Protein 1). Affiliated tissues include skeletal muscle and brain, and related phenotypes are proximal muscle weakness in lower limbs and spastic gait