Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare congenital autosomal recessive disease, presenting in children and adolescents, and characterized by progressive scoliosis along with the absence of conjugate horizontal eye movements and associated with failure of the somatosensory and corticospinal neuronal tracts to decussate in the medulla. The disease is horizontal gaze palsy with progressive scoliosis (Monarch Disease Ontology term MONDO_0011810). Also known as: HGPPS, progressive external ophthalmoplegia and scoliosis.