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|Test group||Chromosome Analysis|
|Performed by||Medical Genomics - Cytogenetics|
|In House Availability||Set up daily, Monday-Friday|
|Method||Fluorescent in-situ hybridization|
|Collection Instructions||Complete and submit a "UCSF Reproductive Genetics Lab Results" or a "UCSF Cytogenetic Requisition" form and send with the samples.
Click here for Cytogenetics Requisition
Keep samples at Room temperature. DO NOT CENTRIFUGE for any reason.
|Container type||Blood: Dark green top
Amniotic fluid: Sterile screw top container
CVS or POC: 15 mL centrifuge tube with transport media (RPMI, FBS, L-Glutamine, Sodium Heparin and PenStrep). Available from Cytogenetics, 415-353-3844.
|Amount to Collect||
|Sample type||Heparinized whole blood, CVS, Amniotic fluid, POC|
|UCSF Rejection Criteria||Insufficient volume; unlabeled tubes; clotted samples; broken, leaking or contaminated tubes; frozen samples.|
|Processing notes||Keep samples at Room temperature. DO NOT CENTRIFUGE for any reason. Send all tubes and completed paperwork asap to the Cytogenetics laboratory at China Basin.|
|Normal range||Normal. See Additional Information|
|Synonyms||Cytogenetic analysis; Karyotype; Karyotyping|
|Turn around times||7-14 days|
|Reflex?||If an abnormality is detected the Director will determine the appropriate additional studies to be performed to characterize the abnormality.
Additional testing may be omitted if specifically requested when the sample is submitted for cytogenetic analysis.
|Additional information||Direct FISH is limited to the detection of aneuploidy (increase or decrease in copy number) of chromosomes 13, 18, 21, X and Y by analyzing 50 INTERPHASE nuclei. A normal result indicates that no numeric abnormality of chromosomes 13, 18, 21, X and Y were identified. It does not rule out the possibility of structural defects or numeric defects in other chromosomes.
DIRECT FISH results are preliminary: G-banded chromosome analysis of 15 colonies or 20 cells remains the standard of care for prenatal diagnosis and all cytogenetic studies. It is also standard of care that no irreversible therapeutic action be initiated on the basis of DIRECT FISH results alone. About one third of all chromosome abnormalities cannot be detected by DIRECT FISH, including structural abnormalities, mosaicism, and numerical
abnormalities of other chromosomes.
"Direct FISH" is the UCSF Cytogenetics name for interphase fluorescence in situ hybridization (FISH) analysis for chromosomes 13, 18, 21, X, and Y. The UCSF lab currently utilizes the FDA-cleared probe set AneuVysionTM from Vysis, Inc. For Direct FISH analysis, 50 cells are examined for each probe.
Each FISH test is developed and its performance characteristics determined by the UCSF Cytogenetics Laboratory as required by CLIA '88 regulations. It has not been cleared or approved for specific uses by the U.S. Food and Drug Administration. All FISH probes undergo internal validation and quality control testing at UCSF Cytogenetics Lab prior to use.
|CPT coding||88275, 88271x3|
|Last Updated||1/22/2014 8:57:05 AM|
If you have additional questions regarding this test, please call: 415-353-1667