Cognitive changes in asymptomatic carriers of the Huntington disease mutation gene.
Huntington disease (HD) is a neurodegenerative disorder due to an excessive number of CAG repeats in the IT15 gene on chromosome 4. Studies of cognitive function in asymptomatic gene carriers have yielded contradictory results. This study compared cognitive performance in 44 subjects with the HD mutation (group of carriers) who had no clinical signs of HD and 39 at-risk individuals without HD mutation (group of non-carriers). Neuropsychological evaluation focused on global cognitive efficiency, psychomotor speed, attentional, executive and memory functions. Significant differences, with lower performances in the group of gene carriers, were detected for some measures of psychomotor speed, attention and executive functioning (all P < 0.01). More differences between groups were observed for memory measures, in particular on the California Verbal Memory Test. Complementing these observations, cognitive scores were correlated with age in the group of gene carriers, but not in the group of non-carriers. This suggests that the cognitive changes precede the appearance of the motor and psychiatric symptoms in HD and that tests proved to be sensitive to early HD deficiencies are better suited than global cognitive efficiency scales to observe them.
Verny
C
C
Centre National de Référence pour les Maladies Neurogénétiques et Mitochondriales de l'Adulte, Centre Hospitalier Universitaire, Angers, France. chverny@chu-angers.fr
Allain
P
P
Prudean
A
A
Malinge
M-C
MC
Gohier
B
B
Scherer
C
C
Bonneau
D
D
Dubas
F
F
Le Gall
D
D
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics; D003072:Cognition Disorders / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D004252:DNA Mutational Analysis; D018450:Disease Progression; D042241:Early Diagnosis; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D006579:Heterozygote; D006801:Humans; D000071058:Huntingtin Protein; D006816:Huntington Disease / Q000150:complications* / Q000235:genetics* / Q000523:psychology; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D009483:Neuropsychological Tests; D009687:Nuclear Proteins / Q000235:genetics; D011237:Predictive Value of Tests; D011379:Prognosis; D011597:Psychomotor Performance / Q000502:physiology; D012680:Sensitivity and Specificity
C086055:HTT protein, human; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins