Invitae FMR1-Fragile X Syndrome and Related Disorders Repeat Expansion Test
Use
The Invitae FMR1-Fragile X Syndrome and Related Disorders Repeat Expansion Test analyzes for trinucleotide (CGG) repeat expansions within the 5′ untranslated region of the FMR1 gene. Pathogenic repeat expansions in FMR1 are the most common cause of Fragile X Syndrome, fragile X-associated tremor/ataxia syndrome, and fragile X-associated primary ovarian insufficiency. The test may help confirm a clinical diagnosis, predict disease prognosis and progression, facilitate early detection of symptoms, or inform family planning and genetic counseling.
Special Instructions
Repeat expansion analysis of the FMR1 gene can inform clinical diagnosis and counseling. Preferred specimens include whole blood, but alternative specimens like saliva and buccal swabs are also accepted. Contact Invitae for specimen collection kits.
Limitations
FMR1 testing is limited to repeat expansion analysis only, not covering coding region sequence, CNV analysis or methylation. Sizing accuracy is +/-1 for 90 repeats. Incidental findings like sex chromosome aneuploidy may appear. Repeat size in peripheral samples may differ from other tissues due to mosaicism. Not validated for low-level mosaic variants.
New York Approved
Methodology
PCR-based (RP-PCR)
Biomarkers
Result Turnaround Time
10-21 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
3mL
Minimum Volume
Not provided
Container
purple-top EDTA tube (K2EDTA or K3EDTA)
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