Prenatal chromosomal microarray analysis | CMA

Test DetailsThermoFisher CytoScan HD assay with genomic DNA extraction to detect small gains and losses across the entire genome. A genomic imbalance is always reported when deletions are greater than 1 Mb and duplications are greater than 2 Mb, unless they represent a region clearly associated with benign copy number polymorphism in multiple independent studies. Regions of homozygosity (ROH) are reported when they are greater than 10 Mb. Deletions smaller than 1 Mb and duplications smaller than 2 Mb may not be reported, unless they involve regions of the genome with established clinical significance. Chromosome analysis will detect large balanced rearrangements.
MethodologyChromosomal microarray analysis
PerformedMonday – Friday
Turnaround21 – 28 days
Specimen RequirementsAmniotic fluid (AF), chorionic villi sampling (CVS), percutaneous umbilical blood sampling (PUBS)
Sample CollectionAF: Discard first 2mL of amniotic fluid. Collect 15-25mL in a sterile syringe. Use sterile technique to transfer to 15mL sterile screw-top plastic conical tubes for transport. Do not centrifuge. CVS: Collect 15-40mg of budding villi in 50mL screw-top plastic conical tubes in sterile transport media (provided by cytogenetics lab). Do not centrifuge. PUBS: Collect 1-3mL in sterile, 15mL sodium heparin (green-top) Vacutainer tube. Collect under ultrasound guidance. Invert tube immediately upon completion of blood collection to prevent formation of clots.
Storage/Transport ConditionsRoom temperature
Unacceptable ConditionsWill not be accepted after three days
Special InstructionsRefrigerate if sample cannot be delivered within 24 hours;
Send to Clinical Support Office (509 S. Euclid Ave., Room 4711 between 8 a.m. and 5 p.m.)
After hours, please send to IOH Core Lab (425 S. Euclid, Room 4701)
Uniquely identify twins/multiples
CPT Code(s)81229 x 1, 88235 x 1, 88291 x 1, 88280 x 1, 88261 x 1