Share
Print CPT 81229
Synonyms
- Reveal® SNP Microarray−Products of Conception (POC)/Tissue
Test Details
Turnaround Time
12 - 18 days
Use
This test will detect chromosomal imbalance that could be associated with developmental delay/congenital anomalies. It provides possible detection of uniparental disomy of any chromosome, the percent and location of homozygosity, including the degree of identity by descent. It will also allow the detection of complete or partial molar pregnancies.
Special Instructions
Pertinent medical findings must accompany test request form. For formalin fixed paraffin embedded blocks or slides, test number will be updated to Microarray-Products of Conception (POC) Reveal® FFPE [511997]. If <8 mg nonfixed tissue is received, sample will be assessed to run on the Oncoscan Microarray platform, and test number adjusted as necessary and client notified.
If prior NIPT studies have been performed, include copy of the report.
Limitations
Unable to determine genotypes on some formalin-fixed tissue (blocks/slides), allowing only genomic dosage to be determined. This SNP assay does not detect balanced rearrangements, low-level mosaicism (<10%), marker chromosomes that only contain heterochromatin or tetraploidy.
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Methodology
SNP microarray analysis is performed using the Cytoscan® HD Accel platform, which uses 743,130 SNP probes and 2,029,441 NPCN probes with a median spacing of 0.818 kb.
Related Documents
For more information, please view the literature below.
SNP Microarray Prenatal POC Clinical Questionnaire
References
Coppinger J, Alliman S, Lamb A, et al. Whole-genome microarray analysis in prenatal specimens identifies clinically significant chromosome alterations without increase in results of unclear significance compared to targeted microarray. Prenatal Diagn. 2009 Dec; 29(12):1156-1166.19795450
Additional Information
The microarray will detect DNA copy-number changes at a threshold >1 Mb for deletions, >2 Mb for duplications.
Specimen Requirements
Information on collection, storage, and volume
Specimen
Preferred nonfixed tissue or products of conception (POC)/placental villus biopsy
Volume
>8 mg tissue
Container
The transport tube (a sterile specimen container with transport medium) is available from Labcorp. Please call customer service at 800-345-4363. (Do not use isotonic saline as a transport medium or urine containers for shipping.) Specialized kits are now available for POC microarray testing. To order, please contact your local Labcorp representative (PeopleSoft No. 89063, catalogue item ID No. 39025G).
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Quantity not sufficient for analysis; necrotic tissue submitted
Collection
Aseptically obtain a small piece of fetal tissue that does not appear necrotic. If specimen is a POC, placental villi or membranes may be the only fetal-derived tissue available, and an effort should be made to submit these tissues rather than maternal decidua.