Monarch Disease Ontology id MONDO_0100149 (PNPLA6-related spastic paraplegia with or without ataxia) is an autosomal recessive, multisystem condition caused by pathogenic variants of the PNPLA6 gene that characterized by peripheral neuropathy, cognitive impairment, lower limb spasticity, muscle weakness, and reduced vibration sense. Additional clinical features may include cerebellar ataxia, hypogonadism, growth hormone deficiency, and hypothyroidism.