This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on ISI (18)  • Contact me when this article is cited  Related Content  • Related article  • Similar articles in this journal  Topic Collections  • Movement Disorders  • Genetic Disorders  • Alert me on articles by topic

Sandra Close Kirkwood, PhD; Eric Siemers, MD; Cherie Bond, BS; P. Michael Conneally, PhD; Joe C. Christian, MD, PhD; Tatiana Foroud, PhD

Arch Neurol. 2000;57:1040-1044.

Objective  To confirm that subtle changes in motor function and reaction time are present in presymptomatic individuals carrying the expanded Huntington disease (HD) allele.

Design  A case-control, double-blind study comparing presymptomatic HD gene carriers (PSGCs) and nongene carriers (NGCs) at risk for HD.

Setting  The Department of Medical and Molecular Genetics at a general clinical research center in a midwestern city.

Participants  Two hundred sixteen individuals at risk for HD who were asymptomatic by self-report and who did not have manifest HD on results of clinical examination, including PSGCs (n = 61) and NGCs (n = 155).

Measures  Molecular testing was used to determine the number of CAG repeats in the HD gene. A quantified neurologic examination and a battery of physiological measures of central nervous system function measuring speed of movement and reaction time were administered.

Results  On neurologic examination, the PSGCs exhibited significantly more definite or possible abnormalities than NGCs for overall oculomotor function, saccade velocity, optokinetic nystagmus, chorea of the extremities, and dystonia of the extremities (P<.05). The PSGCs also had significantly slower performance for auditory reaction time, visual reaction time, visual reaction time with decision, movement time, movement time with decision, and button-tapping time, compared with the NGCs (P<.05).

Conclusions  Subtle changes in motor function, speed of movement, and reaction time are present in HD gene carriers who do not exhibit definite choreiform movements and who do not have sufficient signs to make a clinical diagnosis of HD. In addition, a trend toward slower speed of movement and reaction time was observed among this population as their neurologic abnormalities increased.

From the Department of Medical and Molecular Genetics, Indiana University School of Medicine (Drs Kirkwood, Conneally, Christian, and Foroud and Ms Bond), and Eli Lilly and Company (Dr Siemers), Indianapolis, Ind.

RELATED ARTICLE

Archives of Neurology Reader's Choice: Continuing Medical Education
Arch Neurol. 2000;57(7):1089-1090.
FULL TEXT  

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

White matter connections reflect changes in voluntary-guided saccades in pre-symptomatic Huntington's disease
Kloppel et al.
Brain 2008;131:196-204.
ABSTRACT | FULL TEXT  

Longitudinal Evaluation of "Presymptomatic" Carriers of Huntington's Disease
Witjes-Ane et al.
J. Neuropsychiatry Clin. Neurosi. 2007;19:310-317.
ABSTRACT | FULL TEXT  

Progression of structural neuropathology in preclinical Huntington's disease: a tensor based morphometry study
Kipps et al.
J. Neurol. Neurosurg. Psychiatry 2005;76:650-655.
ABSTRACT | FULL TEXT  

Intact Ability to Learn Internal Models of Arm Dynamics in Huntington's Disease But Not Cerebellar Degeneration
Smith and Shadmehr
J. Neurophysiol. 2005;93:2809-2821.
ABSTRACT | FULL TEXT  

Progression of Symptoms in the Early and Middle Stages of Huntington Disease
Kirkwood et al.
Arch Neurol 2001;58:273-278.
ABSTRACT | FULL TEXT  

Subtle changes among presymptomatic carriers of the Huntington's disease gene
Kirkwood et al.
J. Neurol. Neurosurg. Psychiatry 2000;69:773-779.
ABSTRACT | FULL TEXT