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Updated: Aug 15, 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

[Progressive ataxia and cognitive deficits caused by premutation in the fragile-X-mental retardation gene]

G Roks1, E A Sistermans, L B A de Vries

  • 1St. Elisabeth Ziekenhuis, afd. Neurologie, Postbus 90.151, 5000 LC, Tilburg.

Nederlands Tijdschrift Voor Geneeskunde
|November 10, 2005
PubMed

Insights

Fragile-X-associated tremor/ataxia syndrome (FXTAS) presents with walking difficulty, tremor, and ataxia in older men with an FMR1 gene premutation. Early recognition is crucial for patient care and family genetic counseling.

Area of Science:

  • Neurogenetics
  • Neurology

Background:

  • The FMR1 gene premutation is associated with various neurological disorders.
  • Fragile-X-associated tremor/ataxia syndrome (FXTAS) is a recently described condition affecting older male carriers.

Observation:

  • A 75-year-old man presented with progressive gait issues, intention tremor, ataxia, and cognitive decline.
  • Cerebellar MRI revealed symmetrical hyperintensities in the middle cerebellar peduncles.
  • Genetic analysis confirmed an FMR1 gene premutation with 150-200 CGG repeat expansions.

Findings:

  • The patient's progressive neurological symptoms, including parkinsonism, aligned with the FXTAS clinical phenotype.
  • MRI findings of white matter lesions and cerebellar atrophy are consistent with FXTAS.
  • The patient's condition worsened over two years, necessitating nursing home admission.

Implications:

  • Timely diagnosis of FXTAS is essential for appropriate patient management and support.
  • Identifying FXTAS in male carriers allows for genetic counseling regarding risks to offspring.
  • Female carriers of the FMR1 premutation face an elevated risk of having children with Fragile X syndrome.

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