Digital gait markers to potentially distinguish fragile X-associated tremor/ataxia syndrome, Parkinson's disease, and essential tremor.

Background: Fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disease that affects carriers of a 55-200 CGG repeat expansion in the () gene, may be given an incorrect initial diagnosis of Parkinson's disease (PD) or essential tremor (ET) due to overlapping motor symptoms. It is critical to characterize distinct phenotypes in FXTAS compared to PD and ET to improve diagnostic accuracy. Fast as possible (FP) speed and dual-task (DT) paradigms have the potential to distinguish differences in gait performance between the three movement disorders.

Characterization of the Cerebrospinal Fluid Proteome in Patients with Fragile X-Associated Tremor/Ataxia Syndrome.

Fragile X-associated tremor/ataxia syndrome (FXTAS), first described in 2001, is a neurodegenerative and movement disorder, caused by a premutation in the fragile X mental retardation 1 (FMR1) gene. To date, the biological mechanisms causing this condition are still not well understood, as not all premutation carriers develop FXTAS. To further understand this syndrome, we quantitatively compared the cerebrospinal fluid (CSF) proteome of FXTAS patients with age-matched controls using mass spectrometry.

Global cognitive function and processing speed are associated with gait and balance dysfunction in Parkinson's disease.

Background: Our primary objective was to determine the relationship between global cognitive function and specific domains of gait and balance in a cohort of Parkinson's disease (PD) subjects. In a secondary analysis, we determined whether specific cognitive domains correlated with gait and balance performance.

Methods: Fourteen PD subjects (mean age 61.

X-inactivation in the clinical phenotype of fragile X premutation carrier sisters.

Objective: The purpose of this study is to describe a case series of 4 sisters with discordant clinical phenotypes associated with fragile X-associated tremor/ataxia syndrome (FXTAS) that may be explained by varying CGG repeat sizes and activation ratios (ARs) (the ratio of cells carrying the normal fragile X mental retardation 1 [FMR1] allele on the active X chromosome).

Methods: Four sisters with premutation size FMR1 gene repeats underwent detailed clinical characterization. CGG repeat length was determined by PCR, and AR was determined using a newly developed commercial methylation PCR assay and was compared with the results from Southern blot with densitometric image analysis.

Gait and Functional Mobility Deficits in Fragile X-Associated Tremor/Ataxia Syndrome.

Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" (PM) size CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Cerebellar gait ataxia is the primary feature in some FXTAS patients causing progressive disability. However, no studies have quantitatively characterized gait and mobility deficits in FXTAS.

Characterization and Early Detection of Balance Deficits in Fragile X Premutation Carriers With and Without Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS).

Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" size 55-200 CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Core motor features include cerebellar gait ataxia and kinetic tremor, resulting in progressive mobility disability. There are no published studies characterizing balance deficits in FMR1 premutation carriers with and without FXTAS using a battery of quantitative measures to test the sensory integration underlying postural control, automatic postural reflexes, and dynamic postural stability limits.