Chromosome FISH, Metaphase
Also known as: CHR FISHM
Use
The Chromosome FISH, Metaphase test is primarily used for detecting specific microdeletion or microduplication syndromes through Fluorescence in situ Hybridization (FISH). It involves the use of FISH probes to identify and analyze abnormalities at specific chromosome loci. This test is useful for confirming diagnoses related to chromosomal anomalies, such as Prader-Willi syndrome, Angelman syndrome, and others. Genetic counseling and informed consent are recommended, particularly for New York clients, where consent is mandatory.
Special Instructions
Not provided.
Limitations
The test assesses only the DNA locus complementary to the FISH probe for enumeration and localization. It does not detect low-level mosaicism or copy number variations smaller than the probe target. Aneuploidy and other structural abnormalities are not ruled out. Additional testing might be necessary for comprehensive diagnosis, especially in symptomatic individuals. The assay's accuracy is subject to the type of specimen and probes ordered.
New York Approved
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
Unknown CNV
Copy Number Region
LOINC Codes
- 21717-4 - NF1 gene Mut Anl Bld/T
- 11526-1 - Pathology study
Result Turnaround Time
3-10 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
5 mL
Minimum Volume
2 mL
Container
Green (sodium heparin) tube
Collection Instructions
Collect blood into the specified container. Also acceptable is non-diluted bone marrow aspirate collected in a heparinized syringe.
Storage Instructions
Transport at room temperature.
Causes for Rejection
Paraffin-embedded specimens and clotted specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 48 hours |
| Frozen | Unacceptable |
Other tests from different labs that may be relevant