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Print CPT Contact CPT coding department at 800-222-7566, ext 6-8400. If reflex testing is performed, concomitant CPT codes/charges will apply.
Test Details
Turnaround Time
13 - 24 days
Use
This test is used to evaluate possible chromosomal abnormalities as cause of miscarriage. The SNP assay will detect chromosomal imbalance 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. It will also allow the detection of complete or partial molar pregnancies.
Special Instructions
The microarray reflex is designed for specimens that fail to grow in culture. If tissue fails to grow, reflex to whole genome SNP microarray (Reveal®) targeting 2.8 million copy number and allele-specific genome sites will be initiated. Please include clinical information, previous cytogenetic report or karyotype.
If prior Cell-free DNA/NIPT studies have been performed, include copy of the report.
Call 800-345-4363, if there are any questions. If reflex test is performed, additional charges/CPT code(s) may apply.
Test Includes
Chromosome analysis, SNP microarray reflex
Limitations
Some products of conception may only contain maternal tissue. An option to confirm presence of fetal tissue before testing is available; see Maternal Cell Contamination [511402]. For the SNP assay, it 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
Tissue culture following enzymatic digestion of tissue. Standard harvesting and G-banding procedures are used with 20 metaphases examined and two karyotypes prepared. If tissue fails to grow for cytogenetic analysis, SNP microarray analysis is performed with the remaining fresh tissue using the Cytoscan®HD Accel platform, which uses 743,000 SNP probes and 2,029,441 NPCN probes with a median spacing of 0.818 kb.
For specimens that have failed Cytoscan® HD Accel or specimens that do not have enough DNA to run Cytoscan® HD Accel, SNP microarray analysis is performed using the Oncoscan® FFPE platform. This platform has more than 220,000 SNP probes with a median spacing of 5.0 kb, within the majority of genes.
Related Documents
For more information, please view the literature below.
Specimen Requirements
Information on collection, storage, and volume
Specimen
Tissue, skin, products of conception, placental biopsy
Volume
2 to 4 mm³
Container
Submit biopsies in a sterile tube with sterile Ringer's lactate, Hanks' basal salt solution or Labcorp transport medium.
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 urine containers for shipping.
Saline is not recommended for transport. Do not use urine containers for shipping.
Storage Instructions
Refrigerate; do not freeze.
Causes for Rejection
Upon receipt, suitability of specimen will be determined by the Cytogenetics laboratory.
Collection
Aseptically obtain a small piece of tissue with subepidermal layers. Best results are obtained from placental villi, which remain viable much longer than fetal tissue. This is especially true in stillborn cases in which both cord blood and tissue samples are often not viable. If specimen is a product of conception, submit biopsies in a sterile tube with sterile Ringer's lactate, Hanks' balanced salt solution or Labcorp transport media. Gross contamination, necrotic tissue and specimen in fix cannot be processed.