Related Experiment Video

Updated: Jul 9, 2026

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene
08:22

A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene

Published on: September 16, 2019

[Fragile X premutation presenting as postural tremor and ataxia (FXTAS syndrome)]

P Davous1, R Juntas Morales, C Dupel-Pottier

  • 1Service de Neurologie, Centre Hospitalier Victor-Dupouy, Argenteuil. patrick.davous@ch-argenteuil.fr

Revue Neurologique
|November 23, 2007
PubMed

Insights

Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) is a progressive neurological disorder. Early diagnosis via clinical evaluation and MRI is crucial for patient management and genetic counseling.

Area of Science:

  • Neurology
  • Genetics

Background:

  • FXTAS is a recently identified neurodegenerative disorder primarily affecting older men.
  • It is characterized by progressive motor and cognitive deficits.

Observation:

  • A 58-year-old man presented with postural tremor, ataxia, and cognitive dysfunction.
  • MRI revealed cerebellar atrophy and white matter abnormalities in the brain.
  • Molecular genetics confirmed a CGG trinucleotide repeat expansion.

Findings:

  • The patient's symptoms and imaging findings are consistent with FXTAS.
  • Southern blot analysis identified a 100-120 repeat expansion, confirming the diagnosis.
  • FXTAS may be underdiagnosed, particularly in men over 60.

Implications:

  • Highlights the importance of considering FXTAS in patients with nonspecific neurological symptoms.
  • Emphasizes the diagnostic utility of MRI and molecular testing.
  • Diagnosis has significant implications for genetic counseling of at-risk female relatives.

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