Fragile X Syndrome, Diagnostic
Clinical Genetic Test
offered by
GTR Test Accession: Help GTR000552393.4
Last updated in GTR: 2024-01-15
Last annual review date for the lab: 2023-07-26 LinkOut
At a Glance
Diagnosis; Risk Assessment
Fragile X syndrome; Fragile X-associated tremor/ataxia syndrome; Premature ovarian failure 1
Genes (1): Help
FMR1 (Xq27.3)
Molecular Genetics - Targeted variant analysis: Methylation-specific PCR; Tetra-nucleotide repeat by PCR or Southern Blot
Individuals with unexplained intellectual disabilities, developmental delay, or autism, women …
Not provided
Not provided
Ordering Information
Offered by: Help
Molecular Diagnostic Laboratory
View lab's website
Specimen Source: Help
Who can order: Help
  • Health Care Provider
  • Licensed Physician
  • Nurse Practitioner
  • Physician Assistant
  • Registered Nurse
Test Order Code: Help
Contact Policy: Help
Laboratory can only accept contact from health care providers. Patients/families are encouraged to discuss genetic testing options with their health care provider.
How to Order: Help
Informed consent required: Help
Decline to answer
Pre-test genetic counseling required: Help
Decline to answer
Post-test genetic counseling required: Help
Decline to answer
Recommended fields not provided:
Conditions Help
Total conditions: 3
Condition/Phenotype Identifier
Test Targets
Genes Help
Total genes: 1
Gene Associated Condition Germline or Somatic Allele (Lab-provided) Variant in NCBI
Total methods: 2
Method Category Help
Test method Help
Instrument *
Targeted variant analysis
Methylation-specific PCR
Targeted variant analysis
Tetra-nucleotide repeat by PCR or Southern Blot
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis; Risk Assessment
Target population: Help
Individuals with unexplained intellectual disabilities, developmental delay, or autism, women with primary ovarian insufficiency or failure, premature menopause, or infertility associated with elevated FSH levels before the age of 40 with no known cause, or individuals with late onset intention tremor and/or cerebellar ataxia of unknown origin
Recommended fields not provided:
Technical Information
Availability: Help
Tests performed
Entire test performed in-house

Test performance comments
If 55-90 trinucleotide repeats are detected in females (excluding prenatal specimens), a PCR assay targeting AGG sequences within the CGG repeats is performed at Esoterix Genetic Laboratories, a wholly-owned subsidiary of Laboratory Corporation of America Holdings.
Analytical Validity: Help
The analytical sensitivity of both methylation PCR and PCR analysis is 99% for expansion mutations in the FMR1 gene.
Proficiency testing (PT):
Is proficiency testing performed for this test? Help
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Not provided
Additional Information

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