Detection of early FXTAS motor symptoms using the CATSYS computerised neuromotor test battery.
BACKGROUND
Carriers of the FMR1 premutation allele are at a significantly increased risk for a late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). This disorder is distinct from fragile X syndrome (FXS) in its molecular aetiology and clinical presentation. The primary features of FXTAS are late-onset intention tremor and gait ataxia. Associated features include parkinsonism, neuropsychological dysfunction, autonomic dysfunction and peripheral neuropathy.


OBJECTIVE
To investigate the usefulness of a quantitative neurological test battery implemented through the CATSYS instrument to identify preclinical symptoms of FXTAS.


METHODS
Both premutation carriers with 70-199 repeats (62 men) and their low-repeat allele carrier siblings (27 men), identified through families with an individual affected with FXS, were tested.


RESULTS
As expected, because of its sensitivity, use of the instrument allowed identification of tremor in 23% of men who had not self-reported tremor, and ataxia in 30% of men who had not self-reported ataxia. Among subjects with self-reported tremor and ataxia, we found significant concordance between measures of the CATSYS system and the self-report.


CONCLUSIONS
Rates of these traits among premutation carriers and low-repeat allele carrier siblings could be identified, and are presented in this paper, along with the minimum estimates of age-related prevalence.
Allen
E G
EG
Emory University, Department of Human Genetics, 615 Michael Street, Suite 301, Whitehead Research Building, Atlanta, Georgia 30322, USA. egraves@genetics.emory.edu
Juncos
J
J
Letz
R
R
Rusin
M
M
Hamilton
D
D
Novak
G
G
Shubeck
L
L
Tinker
S W
SW
Sherman
S L
SL
D001259:Ataxia / Q000175:diagnosis* / Q000209:etiology; D003936:Diagnosis, Computer-Assisted; D005600:Fragile X Syndrome / Q000175:diagnosis; D005820:Genetic Testing; D020271:Heredodegenerative Disorders, Nervous System / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D009048:Motor Skills; D009460:Neurologic Examination; D015995:Prevalence; D014202:Tremor / Q000175:diagnosis* / Q000209:etiology