Minimum prevalence of spinocerebellar ataxia 17 in the north east of England.
OBJECTIVE
To determine the minimum prevalence of spinocerebellar ataxia type 17 (SCA17) in the north east of England.


METHODS
A defined region containing 2,516,500 individuals with 192 families with undiagnosed ataxia, 90 patients with a Huntington's disease-like phenotype and 292 controls. The number of (CAG/CAA)(n) repeats in the SCA17/TBP gene was determined by fluorescent PCR and sequenced in affected individuals.


RESULTS
The mean repeat size for 584 control alleles was 34 (S.D.=3.58), ranging from 25 to 40. Two index cases had larger alleles with repeat lengths greater than the control range. Affected family members presented in adult life with ataxia followed by extrapyramidal features and cognitive impairment. In one family 44 repeats were associated with a younger age of onset than has been previously described.


CONCLUSIONS
The minimum prevalence of SCA17 in the north east of England was 0.16/100,000 (upper 95% confidence interval 0.31/100,000).
Craig
Kate
K
Neurology, The University of Newcastle upon Tyne, United Kingdom.
Keers
Sharon M
SM
Walls
Timothy J
TJ
Curtis
Anne
A
Chinnery
Patrick F
PF
D000293:Adolescent; D000328:Adult; D000067696:Ataxin-1; D000067528:Ataxins; D001284:Atrophy / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D001480:Basal Ganglia Diseases / Q000453:epidemiology / Q000235:genetics; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000453:epidemiology / Q000235:genetics; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004252:DNA Mutational Analysis; D004739:England / Q000453:epidemiology; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005820:Genetic Testing; D005838:Genotype; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D010641:Phenotype; D020754:Spinocerebellar Ataxias / Q000453:epidemiology* / Q000235:genetics*; D018911:Trinucleotide Repeats / Q000235:genetics
C000593749:ATXN1 protein, human; D000067696:Ataxin-1; D000067528:Ataxins; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins