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

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Cranial and hand skeleton in fragile X syndrome

I Kjaer1, H Hjalgrim, B G Russell

  • 1Department of Orthodontics, School of Dentistry, Faculty of Health Sciences, University of Copenhagen, Denmark. ik@odont.ku.dk

American Journal of Medical Genetics
|April 12, 2001
PubMed

Insights

Prenatal skeletal deviations in radiographs are present in most males with fragile X syndrome. Skeletal analysis may aid in early fragile X syndrome diagnosis and phenotypic classification.

Area of Science:

  • Medical Imaging
  • Genetics
  • Pediatrics

Background:

  • Fragile X syndrome (FXS) is a genetic disorder associated with intellectual disability.
  • Early diagnosis of FXS is crucial for timely intervention.
  • Prenatal detection of skeletal anomalies could improve diagnostic capabilities.

Purpose of the Study:

  • To investigate prenatal skeletal deviations in children and young adults with fragile X syndrome.
  • To assess the potential of skeletal analysis for early FXS diagnostics.
  • To correlate prenatal findings with postnatal skeletal development.

Main Methods:

  • Analysis of craniofacial profile and hand radiographs from six males with FXS (ages 2y9m to 20y3m).
  • Evaluation of specific skeletal features including nasal bone, sella turcica, cervical spine, and carpal bones.
  • Assessment of skeletal maturity and comparison with prenatal observations.

Main Results:

  • Normal nasal bone morphology observed in all cases.
  • Sella turcica abnormalities (oblique anterior wall, short dorsum sellae) noted in 4 out of 5 analyzable cases.
  • Cervical spine anomalies (body fusion, short arcus) found in one case.
  • Deviant carpal bone location observed in 5 out of 6 cases.
  • Delayed skeletal maturity noted in all participants.
  • Prenatal skeletal deviations were confirmed postnatally in 5 out of 6 FXS males.

Conclusions:

  • Prenatally identified skeletal developmental deviations persist in most males with fragile X syndrome.
  • Skeletal analysis, including hand and craniofacial radiographs, shows potential for improving early FXS diagnosis.
  • Consideration of skeletal analysis in the phenotypic classification of FXS is recommended.

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