Three children in a Jordanian family, with consanguinous parents, who met the Stark and Moersch (1945) criteria for the diagnosis of primary lateral sclerosis (PLS) are reported from the King Faisal Specialist Hospital and Research Centre, and King Khalid Eye Specialist Hospital, Riyadh, Saudi Arabia, and Northwestern University Medical School, Chicago, Illinois, USA. In addition they had a diffuse conjugate saccadic gaze paralysis, especially on down-gaze. A chronic progressive weakness beginning in late infancy, associated with spastic quadriplegia and pseudobulbar palsy, led to wheelchair dependence by adolescence and later loss of speech, while intellect was preserved. CT, MRI, EEG, EMG, NCS, and laboratory tests, including enzyme and amino acid assays, were normal. All patients had absent transcranial magnetic motor-evoked potentials in abductor pollicis and anterior tibial brevis muscles. Molecular testing, using DNA blood extracts, showed no linkage to chromosome 2q33 juvenile amyotrophic lateral sclerosis locus, the 8q recessive familial spastic paraplegia locus, or the 5ql3 spinal muscular atrophy locus. The clinical course and absence of specific neuropathological etiologies support the diagnosis of familial, autosomal recessive, primary lateral sclerosis. 
COMMENT. All three of these patients were referred with a diagnosis of cerebral palsy, despite the familial and progressive nature of the disorder. The authors cite only one other case of childhood primary lateral sclerosis in the literature. The present report is presented as the first of familial cases. Ford FR refers to cases of hereditary spastic paraplegia in children with degeneration confined to the pyramidal tracts.