| A rare pure or complex subtype of hereditary spastic paraplegia, with highly variable phenotype. Typical characteristics include childhood-onset of minimally progressive bilateral mainly symmetric lower limb spasticity and weakness, associated with pes cavus, diminished vibration sense, sphincter disturbances and/or urinary bladder hyperactivity. Additional associated manifestations may include scoliosis, mild intellectual disability, optic atrophy, axonal motor neuropathy and/or distal amyotrophy. Caused by heterozygous mutation in the ATL1 gene on chromosome 14q22. |