Spinocerebellar ataxia type 8 in Scotland: frequency, neurological, neuropsychological and neuropsychiatric findings

• Published in: Acta neurologica Scandinavica Vol. 117; no. 1; pp. 41 - 48
• Main Authors: Torrens, L., Burns, E., Stone, J., Graham, C., Wright, H., Summers, D., Sellar, R., Porteous, M., Warner, J., Zeman, A.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.01.2008; Blackwell
• Subjects: Adult; Aged; Biological and medical sciences; Carbohydrates (enzymatic deficiencies). Glycogenosis; Cerebellum - pathology; Cerebellum - physiopathology; Cognition - physiology; Cognition Disorders - diagnosis; Cognition Disorders - etiology; Cognition Disorders - physiopathology; DNA Mutational Analysis; Errors of metabolism; Female; Gene Frequency; Genetic Markers; Genetic Predisposition to Disease - genetics; Genetic Testing; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; higher cortical functions; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Mental Disorders - diagnosis; Mental Disorders - etiology; Metabolic diseases; Middle Aged; Nerve Tissue Proteins - genetics; Nervous system (semeiology, syndromes); neurodegenerative disorders; Neurology; Neuropsychological Tests; neuropsychology; RNA, Long Noncoding; RNA, Untranslated; Scotland; Spinocerebellar Ataxias - complications; Spinocerebellar Ataxias - genetics; Spinocerebellar Ataxias - psychology; spinocerebellar atrophy; Trinucleotide Repeat Expansion - genetics; Scotland; Atrophy; spinocerebellar atrophy; Nervous system diseases; Spinocerebellar ataxia; Central nervous system disease; neuropsychology; Degenerative disease; neurodegenerative disorders; Genetic disease; higher cortical functions
• ISSN: 0001-6314; 1600-0404
• DOI: 10.1111/j.1600-0404.2007.00904.x

Objectives –  The objectives of this study were to: (i) establish whether the spinocerebellar ataxia type 8 (SCA 8) expansion is associated with ataxia in Scotland; (ii) test the hypothesis that SCA 8 is associated with neuropsychological impairment; and (iii) review neuroradiological findings in SCA 8. Methods –  The methods included: (i) measurement of SCA 8 expansion frequencies in ataxic patients and healthy controls; (ii) comprehensive neuropsychological assessment of patients with SCA 8 and matched controls, neuropsychiatric interview; and (iii) comparison of patient and matched control magnetic resonance imaging (MRI) scans. Results –  (i) 10/694 (1.4%) unrelated individuals with ataxia had combined CTA/CTG repeat expansions >100 compared to 1/1190 (0.08%) healthy controls (P < 0.0005); (ii) neuropsychological assessment revealed a dysexecutive syndrome among SCA 8 patients, not readily explained by motor or mood disturbance; neuropsychiatric symptoms occurred commonly; (iii) cerebellar atrophy was the only salient MRI abnormality in the patient group. Conclusions –  The SCA 8 expansion is associated with ataxia in Scotland. The disorder is associated with a dysexecutive syndrome.