GTR Home > Tests > FMR1-Related Disorders


Test name


FMR1-Related Disorders

Purpose of the test


This is a clinical test intended for Help: Diagnosis



3 conditions tested. Click Indication tab for more information.


Molecular Genetics
MMethylation analysis
Trinucleotide repeat by PCR or Southern Blot
TTargeted variant analysis
Trinucleotide repeat by PCR or Southern Blot

Summary of what tested

1 genes and variants. Click Methodology tab for more information.

Genes and variants

Clinical validity


More than 99% of individuals with fragile X syndrome have a loss-of-function mutation in FMR1 caused by an increased number of CGG trinucleotide repeats (typically >200) accompanied by aberrant methylation of FMR1.


Not provided

Clinical utility


Not provided

How to order


Order URL Help:

Test services

  • Custom mutation-specific/Carrier testing

Clinical resources

Practice guidelines

  • ACMG, 2008
    Clinical significance of tri-nucleotide repeats in Fragile X testing: A clarification of American College of Medical Genetics guidelines
  • ACMG, 2008
    Clinical genetics evaluation in identifying the etiology of autism spectrum disorders
  • ACMG, 2005
    Fragile X syndrome: Diagnostic and carrier testing
  • ACMG, 2001
    Technical Standards and Guidelines for Fragile X: The First of a Series of Disease-Specific Supplements to the Standards and Guidelines for Clinical Genetics Laboratories of the American College of Medical Genetics
  • EuroGenetest, 2011
    Clinical utility gene card for: fragile X mental retardation syndrome, fragile X-associated tremor/ataxia syndrome and fragile X-associated primary ovarian insufficiency.

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