Test Details
Methodology
Fluorescence in situ hybridization (FISH), direct harvest of trophoblasts and in situ culture from enzymatic dissociated mesenchymal cells
An abnormal FISH result will reflex to cultured G-banded chromosome analysis. A normal FISH result will reflex to SNP microarray analysis, which is performed from uncultured cells using the Cytoscan® HD platform, which uses more than 743,000 SNP probes and 1,953,000 NPCN probes with a median spacing of 0.88 kb. If DNA yield on uncultured cells is inadequate, analysis will be performed on cultured cells. If cultures are needed, additional days will be required to complete testing.
Result Turnaround Time
10 - 13 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
FISH allows for rapid identification of common prenatal aneuploidy (specific for X, Y, 13, 18, 21). An abnormal result reflexes to karyotyping (G-band chromosome analysis). A normal FISH result reflexes to the SNP assay, which will detect chromosomal imbalances that could be associated with developmental delay/congenital anomalies. It provides detection of possible uniparental disomy of any chromosome, the percent and location of homozygosity, including the degree of identity by descent.
Special Instructions
Pertinent medical history and test request form must accompany request for chromosome analysis. Include name, age, gestational age and indication for procedure. If abnormal FISH result, then reflex to chromosome karyotyping, if normal FISH result then reflex to microarray testing. A completed Informed Consent and Prenatal Chromosome SNP Microarray Questionnaire form should accompany specimens. Call 800-345-4363 to request form. Concurrent maternal contamination (MCC) studies are recommended.
Limitations
FISH detects only the most common prenatal aneusomies. All abnormal FISH results should have cytogenetic confirmation. MCC studies are recommended. FISH will not detect balanced rearrangements and may not detect low level mosaicism. Extensive maternal cell contaminaton will limit the sensitivity of the assay. The SNP assay does not detect balanced rearrangements, low-level mosaicism (<10%), marker chromosomes that only contain heterochromatin or tetraploidy.
The SNP assay does not detect balanced rearrangements, low-level mosaicism (<10%), marker chromosomes that only contain heterochromatin, or tetraploidy.
Specimen Requirements
Specimen
Chorionic villi
Volume
20-30 mg
Minimum Volume
20 mg
Container
The CVS transport tube (a sterile specimen container with transport medium) is available from Labcorp. Please call customer service at 800-345-4363.
Collection Instructions
Specimen is collected in syringe (transabdominal) or catheter (transcervical) and transferred by flushing with the media from the sterile container back into it. After collecting the specimen, wash with sterile saline solution (NaCl 0.95%) containing sodium heparin (two to three drops of sodium heparin in 10 mL of saline). Carefully transfer the specimen, into the CVS transport tube, using a sterile Pasteur pipette or a sterile fine needle forceps. Be sure to fill transport tubes completely with media. Samples from twin (multiple) pregnancies should be appropriately labeled and placed in separate transport containers with a separate request form for each twin.
Storage Instructions
Maintain specimen at room temperature and transport to the Cytogenetics Laboratory immediately. Do not freeze. Refrigerate if sterility is questioned or if sample cannot be shipped within 24 hours.
Causes for Rejection
No villi submitted or low volume in specimen; improper labeling; frozen or contaminated villi; specimen placed in fixative; wrong specimen or maternal decidual received
References
LOINC® Map
Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
---|---|---|---|---|---|---|
511625 | FISH CVS Rfx CMA or Chromo | 510803 | Cells Counted | 64089-6 | ||
511625 | FISH CVS Rfx CMA or Chromo | 510804 | Cells Analyzed | 64086-2 | ||
511625 | FISH CVS Rfx CMA or Chromo | 510805 | Cytogenetic Diagnosis | 57318-8 | ||
511625 | FISH CVS Rfx CMA or Chromo | 510958 | Cytogenetic Interpretation | 62365-2 | ||
511625 | FISH CVS Rfx CMA or Chromo | 510807 | Specimen Type | 31208-2 | ||
511625 | FISH CVS Rfx CMA or Chromo | 510959 | Director Review: | 72486-4 | ||
511625 | FISH CVS Rfx CMA or Chromo | 511578 | Reflex | N/A | ||
511625 | FISH CVS Rfx CMA or Chromo | 512123 | 11502-2 | |||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510803 | |||||
Result Code Name | Cells Counted | |||||
UofM | ||||||
Result LOINC | 64089-6 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510804 | |||||
Result Code Name | Cells Analyzed | |||||
UofM | ||||||
Result LOINC | 64086-2 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510805 | |||||
Result Code Name | Cytogenetic Diagnosis | |||||
UofM | ||||||
Result LOINC | 57318-8 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510958 | |||||
Result Code Name | Cytogenetic Interpretation | |||||
UofM | ||||||
Result LOINC | 62365-2 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510807 | |||||
Result Code Name | Specimen Type | |||||
UofM | ||||||
Result LOINC | 31208-2 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 510959 | |||||
Result Code Name | Director Review: | |||||
UofM | ||||||
Result LOINC | 72486-4 | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 511578 | |||||
Result Code Name | Reflex | |||||
UofM | ||||||
Result LOINC | N/A | |||||
Order Code | 511625 | |||||
Order Code Name | FISH CVS Rfx CMA or Chromo | |||||
Order Loinc | ||||||
Result Code | 512123 | |||||
Result Code Name | ||||||
UofM | ||||||
Result LOINC | 11502-2 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510216 | Chromosome Microarray | N/A | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510216 | |||||
Result Name | Chromosome Microarray | |||||
UofM | ||||||
Result LOINC | N/A |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510043 | Specimen Type | 31208-2 | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510043 | |||||
Result Name | Specimen Type | |||||
UofM | ||||||
Result LOINC | 31208-2 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510044 | # of Genotyping Targets | N/A | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510044 | |||||
Result Name | # of Genotyping Targets | |||||
UofM | ||||||
Result LOINC | N/A |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510045 | Array Type | N/A | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510045 | |||||
Result Name | Array Type | |||||
UofM | ||||||
Result LOINC | N/A |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510048 | Diagnosis | 48000-4 | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510048 | |||||
Result Name | Diagnosis | |||||
UofM | ||||||
Result LOINC | 48000-4 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510049 | Interpretation | 50398-7 | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510049 | |||||
Result Name | Interpretation | |||||
UofM | ||||||
Result LOINC | 50398-7 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 510061 | Director Review | 48672-0 | |
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 510061 | |||||
Result Name | Director Review | |||||
UofM | ||||||
Result LOINC | 48672-0 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 510098 | Chromosome Microarray | 512123 | 11502-2 | ||
Reflex 1 | ||||||
Order Code | 510098 | |||||
Order Name | Chromosome Microarray | |||||
Result Code | 512123 | |||||
Result Name | ||||||
UofM | ||||||
Result LOINC | 11502-2 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510052 | Cells Counted | 64089-6 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510052 | |||||
Result Name | Cells Counted | |||||
UofM | ||||||
Result LOINC | 64089-6 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510054 | Cells Analyzed | 64086-2 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510054 | |||||
Result Name | Cells Analyzed | |||||
UofM | ||||||
Result LOINC | 64086-2 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510055 | Cells Karyotyped | 64085-4 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510055 | |||||
Result Name | Cells Karyotyped | |||||
UofM | ||||||
Result LOINC | 64085-4 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510056 | GTG Band Resolution | 64087-0 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510056 | |||||
Result Name | GTG Band Resolution | |||||
UofM | ||||||
Result LOINC | 64087-0 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510057 | Cytogenetic Diagnosis | 33774-1 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510057 | |||||
Result Name | Cytogenetic Diagnosis | |||||
UofM | ||||||
Result LOINC | 33774-1 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510989 | Cytogenetic Interpretation | 64088-8 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510989 | |||||
Result Name | Cytogenetic Interpretation | |||||
UofM | ||||||
Result LOINC | 64088-8 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 511581 | Specimen Type | 31208-2 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 511581 | |||||
Result Name | Specimen Type | |||||
UofM | ||||||
Result LOINC | 31208-2 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 510991 | Director Review: | 48672-0 | |
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 510991 | |||||
Result Name | Director Review: | |||||
UofM | ||||||
Result LOINC | 48672-0 |
Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
---|---|---|---|---|---|---|
Reflex 1 | 511579 | Chromosome, Chorionic Villus | 512123 | 11502-2 | ||
Reflex 1 | ||||||
Order Code | 511579 | |||||
Order Name | Chromosome, Chorionic Villus | |||||
Result Code | 512123 | |||||
Result Name | ||||||
UofM | ||||||
Result LOINC | 11502-2 |