XSense(R), Fragile X with Reflex
GTR Test Accession: Help GTR000508090.8
Last updated in GTR: 2023-07-03
Last annual review date for the lab: 2023-07-07 LinkOut
At a Glance
Diagnosis; Risk Assessment; Screening
Fragile X syndrome; Fragile X-associated tremor/ataxia syndrome
Genes (1): Help
FMR1 (Xq27.3)
Molecular Genetics - Methylation analysis: PCR
Individuals with intellectual disability and/or autism, individuals with a family …
Not provided
Not provided
Ordering Information
Offered by: Help
Quest Diagnostics Nichols Institute San Juan Capistrano
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View lab's test page
Test short name: Help
Specimen Source: Help
Who can order: Help
  • Health Care Provider
  • Licensed Physician
Test Order Code: Help
16313; fetal samples use test code 16300
View other test codes
CPT codes: Help
**AMA CPT codes notice
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

This test is included in the following test codes:
Fragile X w/ reflex to chromosome analysis use test code: 16326
Prenatal carrier screen: test code 90949
Prenatal carrier panel: test code 93349
QHerit™ Expanded Carrier Screen: 94372
fetal samples require documentation of familial fragile X results. Please …
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Order URL
Test development: Help
Test developed by laboratory (no manufacturer test name)
Informed consent required: Help
Based on applicable state law
Test strategy: Help
Pre-test genetic counseling required: Help
Post-test genetic counseling required: Help
Recommended fields not provided:
Conditions Help
Total conditions: 2
Condition/Phenotype Identifier
Test Targets
Genes Help
Total genes: 1
Gene Associated Condition Germline or Somatic Allele (Lab-provided) Variant in NCBI
Total methods: 1
Method Category Help
Test method Help
Instrument *
Methylation analysis
* Instrument: Not provided
Clinical Information
Test purpose: Help
Diagnosis; Risk Assessment; Screening
Target population: Help
Individuals with intellectual disability and/or autism, individuals with a family history of fragile X syndrome (FXS) or other FMR1-related disorders, females with primary ovarian insufficiency (POI), and individuals with symptoms characteristic of fragile X-associated tremor/ataxia syndrome (FXTAS)
Variant Interpretation:
What is the protocol for interpreting a variation as a VUS? Help
not applicable

Are family members with defined clinical status recruited to assess significance of VUS without charge? Help
not applicable

Will the lab re-contact the ordering physician if variant interpretation changes? Help
Not provided.
Recommended fields not provided:
Technical Information
Availability: Help
Tests performed
Entire test performed in-house
Analytical Validity: Help
Analytical sensitivity and specificity = 99%
Proficiency testing (PT):
Is proficiency testing performed for this test? Help

Method used for proficiency testing: Help
Formal PT program

PT Provider: Help
American College of Medical Genetics / College of American Pathologists, ACMG/CAP
Software used to interpret novel variations Help
not applicable

Laboratory's policy on reporting novel variations Help
not applicable
Recommended fields not provided:
Regulatory Approval
FDA Review: Help
Category: FDA exercises enforcement discretion
Additional Information

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