Chromosome FISH, Chorionic Villus with Reflex to Chromosome Analysis or Genomic Microarray
Also known as: CVS F RFLX
Use
The primary clinical utility of this test is to rapidly detect aneuploidy involving chromosomes 13, 18, 21, X, and Y in chorionic villus samples. If the FISH results are abnormal, the test reflexes to chromosome analysis to determine the mechanism. In the case of normal FISH results, the specimen reflexes to genomic microarray analysis. This approach is valuable for prenatal diagnoses to identify potential chromosomal abnormalities early in pregnancy, aiding in clinical decision-making.
Special Instructions
Not provided.
Limitations
This FISH test does not detect structural chromosome abnormalities, mosaicism, or non-standard numerical chromosome abnormalities beyond chromosomes 13, 18, 21, X, and Y. There is also a potential for false-positive or false-negative results. The test results should not be used as a sole basis for irreversible therapeutic decisions according to the American College of Medical Genetics guidelines. Reflex testing to chromosome analysis may yield additional insights, although chromosome analysis itself has its limitations in detecting small rearrangements or low-level mosaicism.
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
LOINC Codes
- 55193-7 - Chrom analy interphase CVS FISH-Imp
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (Unknown)
Volume
20-30 mg
Minimum Volume
10 mg
Container
Sterile, screw-top container filled with tissue culture transport medium
Collection Instructions
Thaw media prior to collection. If cytogenetics tissue media is not available, collect in plain RPMI, Hanks solution, saline, or Ringer's
Storage Instructions
Transport at room temperature.
Causes for Rejection
Specimens preserved in formalin.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 48 hours |
| Frozen | Unacceptable |
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