SNP Microarray−Products of Conception (POC)/Tissue (Reveal®)

CPT 81229
Synonyms
  • Reveal® SNP Microarray−Products of Conception (POC)/Tissue

Test Details

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, please use Microarray-Products of Conception (POC) Reveal® FFPE [511997].

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 platform, which uses more than 743,000 SNP probes and 1,953,000 NPCN probes with a median spacing of 0.88 kb.

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; formalin-fixed paraffin-embedded tissue; (Samples received in fixative are subject to additional charge for histopathology processing and reporting); unstained tissue slides

Volume

>2 to 4 mm³ tissue; 10 unstained tissue slides

Container

Sterile container containing sterile Ringer's lactate or Hanks' balanced salt solution or transport medium provided by the cytogenetics laboratory. (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: 89063, Catalogue 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.