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Aneuvysion FISH 18/XY

Item Value
Available Stat? No
Test code A18XY
Test group FISH
Performed by Medical genomics - Cytogenetics
In House Availability Set up daily, Monday - Friday
Method Fluorescent in-situ hybridization (FISH)
Container type
Blood Dark green top
Amniotic fluid Sterile screw top container
CVS or POC 15 mL centrifuge tube with transport media (Avaialable from Cytogenetics: 353-4844
Amount to Collect
Whole blood, child or adult 10 mL
Whole blood, infant 3 mL
Amniotic fluid 10 mL
CVS 10 mg
POC 10 mg
Sample type Heparinized whole blood, Amniotic fluid, CVS, POC
Preferred volume
Whole blood, child or adult 10 mL
Whole blood, infant 3 mL
Amniotic fluid 10 mL
CVS 10 mg
POC 10 mg
Min. Volume
Whole blood, child or adult 3 mL
Whole blood, infant 1 mL
Amniotic fluid 5 mL
CVS 5 mg
POC 5 mg
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
Synonyms AV 18/XY; Direct aneuploidy FISH 18/XY
Stability 1-2 days
Turn around times 2-3 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. This FISH contain 18/XY individual probe set only, 50 interphase nuclei will be analyzed. A normal result indicates that no numeric abnormality of chromosomes 18, 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. This probe will contain only 18 and XY, The UCSF lab currently utilizes the FDA-cleared probe set AneuVysionTM from Vysis, Inc. For this Direct FISH analysis, 50 cells are examined for this 18/XY probe set.

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 88271 x3, 88275, 88291
LDT or Mod FDA? Yes
Last Updated 5/28/2016 5:07:11 PM
Entry Number 1624
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