title: Pathogenesis of clinical signs in recessive ataxia with saccadic intrusions.
abstract: We describe a family of Slovenian descent with progressive ataxia, corticospinal signs, axonal sensorimotor neuropathy, and disruption of visual fixation by saccadic intrusions. Chromosome mapping indicated a mutation on 1p36, and this recessive disorder has been designated spinocerebellar ataxia with saccadic intrusions. Affected patients showed overshooting horizontal saccades, macrosaccadic oscillations, and increased velocity of larger saccades; other eye movements were normal. Slowed conduction in axons that are selectively vulnerable to the molecular defect could explain both the sensorimotor neuropathy and the saccadic disorder, which would be caused by delayed feedback control because of slow conduction in cerebellar parallel fibers.
authors.affiliation: Department of Neurology, Veterans Affairs Medical Center, and University Hospitals, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH 44106-5040, USA.
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Swartz
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
authors.forename: Irina
authors.initials: I
authors.lastname: Bespalova
authors.forename: Margit
authors.initials: M
authors.lastname: Burmeister
authors.forename: Eugene
authors.initials: E
authors.lastname: Dulaney
authors.forename: Farrel R
authors.initials: FR
authors.lastname: Robinson
authors.forename: R John
authors.initials: RJ
authors.lastname: Leigh
mesh_terms: D000328:Adult; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D016001:Confidence Intervals; D005260:Female; D005808:Genes, Recessive; D006801:Humans; D008297:Male; D008875:Middle Aged; D015835:Ocular Motility Disorders / Q000150:complications / Q000235:genetics* / Q000473:pathology; D013132:Spinocerebellar Degenerations / Q000150:complications / Q000235:genetics* / Q000473:pathology