Reveal® SNP Microarray – Prenatal

Test Details

Turnaround Time

8 - 15 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

This test detects chromosomal imbalance that could be associated with developmental delay/congenital anomalies. It provides detection of uniparental disomy of any chromosome, the percentage and location of homozygosity, including the degree of identity by descent.

Special Instructions

When ordering chromosome analysis with reflex to microarray if chromosome analysis is normal, provide at least 30 cc of amniotic fluid or 30 mg of uncultured CVS An increase in the turnaround time and additional charges will apply for the microarray A Clinical Questionnaire for Reveal SNP Microarray - Prenatal must be completed. If prior NIPT or maternal serum screening studies have been performed, include copy of report.

Limitations

This assay does not detect balanced rearrangements and may not detect low-level mosaicism.

Methodology

Whole genome SNP-based copy-number microarray analysis targeting 2.695 million copy-number and allele-specific genome sites from uncultured cells. If DNA yield on uncultured cells is inadequate, analysis will be performed on cultured cells.

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.PubMed 19795450 Wapner R. A multicenter, prospective, masked comparison of chromosomal microarray with standard karyotyping for routine and higher risk prenatal diagnosis. Abstract 1. Am J Ob Gyn Supplement. to Jan 2012.

Specimen Requirements

Information on collection, storage, and volume

Specimen

Cultured CVS or amniocytes

Volume

>30 cc of amniotic fluid or 30 mg of uncultured CVS

Container

Two confluent T-25 flasks

Storage Instructions

Maintain specimen at room temperature

Causes for Rejection

Quantity not sufficient for analysis (less than 10 mL of amniotic fluid or DNA quantity

Collection

Discard first 2 mL of fluid aspirated to avoid maternal cell contamination. Specimen is collected in a 20 mL sterile syringe and transferred aseptically to sterile tubes