Genetic Carrier Screen, (CF, FXS, and SMA) with Reflex to Methylation
Also known as: CF FX SMA
Use
This genetic carrier screening test is specifically designed for women who are pregnant or planning to become pregnant. It provides carrier status for three genetic conditions: cystic fibrosis (CF), fragile X syndrome (FXS), and spinal muscular atrophy (SMA). The test is important for assessing the reproductive risk for these conditions, enabling informed decision-making and family planning. Although it is not meant for men, as FXS carrier screening is not indicated for them, it gives critical information for preconception and prenatal genetic counseling.
Special Instructions
The test is not suitable for diagnostic purposes in individuals presenting symptoms of CF, FXS, or SMA. For individuals needing carrier screening for just one of these conditions, separate, specific tests are recommended instead: Cystic Fibrosis (CFTR) Expanded Variant Panel, Spinal Muscular Atrophy (SMA) Copy Number Analysis, or Fragile X (FMR1) with Reflex to Methylation Analysis. New York state approval status applies, and informed consent is required for genetic testing in NY.
Limitations
This test might not detect rare FMR1 variants causing less than 1% of FXS cases. Other limitations include potential diagnostic errors due to rare sequence variations, and it does not assess AGG trinucleotide interruptions in the FMR1 CGG repeat. For CF, only specified CFTR variants are tested, and it cannot detect other pathogenic variants outside this range. Similarly, for SMA, the test won't identify single nucleotide variants, small deletions, or intronic variations beyond the tested regions. Results should be interpreted in conjunction with clinical findings and possibly further genetic consultation.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 45321-7
- 45322-5
- 41107-4
- 36913-2
- 66746-9
- 31208-2
- 75325-1
- 35462-1
- 54449-4
- 82155-3
- 49857-6
- 42938-1
- 42939-9
- 21656-4
- 21654-9
Result Turnaround Time
4-14 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
5 mL
Minimum Volume
3 mL
Container
Lavender (K2EDTA) or Pink (K2EDTA)
Storage Instructions
Refrigerated
Causes for Rejection
Plasma or serum. Specimens collected in sodium heparin, yellow (ACD solution A), or lithium heparin tubes. Frozen specimens in glass collection tubes.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 1 week |
| Frozen | unacceptable |