Ophthalmologic features of the common spinocerebellar ataxias.
OBJECTIVE
The spinocerebellar ataxias (SCAs) are a phenotypically and genetically diverse group of autosomal dominant disorders that cause pathological degeneration in the cerebellum, brainstem, and retina, resulting in a wide variety of ophthalmologic signs and symptoms.


RESULTS
The genetic discrimination of the SCAs has advanced dramatically over the past decade. The most common genetic (mutational) mechanism for the SCAs is an abnormal expansion to a stretch of glutamine amino acid residues (polyglutamine tract) encoded by any of several SCA-causing genes. Knowledge regarding the pathophysiology of polyglutamine-expansion-induced protein dysfunction is an area of intense investigation.


CONCLUSIONS
The ophthalmologist may be the first to encounter a patient with SCA, and a review of the most common genetic subtypes of this disorder is helpful in diagnosis and management.
Pula
John H
JH
University of Illinois College of Medicine at Peoria, Department of Neurology and Neuro-ophthalmology, Peoria, USA.
Gomez
Christopher M
CM
Kattah
Jorge C
JC
D006801:Humans; D015840:Oculomotor Nerve Diseases / Q000175:diagnosis* / Q000235:genetics; D020754:Spinocerebellar Ataxias / Q000175:diagnosis* / Q000235:genetics