Prenatal/POC Whole Genome Chromosomal Microarray (CMA)
Use
Chromosomal microarray (CMA) in a prenatal setting identifies clinically relevant copy number changes and uniparental disomy (UPD) with higher resolution and sensitivity than conventional karyotyping. The whole-genome CMA includes ≈2.67 million probes (1.9 million non‑polymorphic CNV probes and 750,000 SNP probes) across the genome to detect deletions ≥25 kb, duplications ≥50 kb, and regions of homozygosity (ROH). It aids in diagnosing fetal chromosomal imbalances and supports maternal cell contamination (MCC) detection concurrently.
Special Instructions
A Prenatal Genetics Test Requisition Form (Test Code 460) is required. If sufficient fetal material is submitted, most testing—including reflex to exome if needed—can be performed concurrently on the same sample. Parental samples (maternal and paternal blood or buccal) are required for MCC studies and trio analysis.
Limitations
CMA cannot detect balanced chromosomal rearrangements (e.g., inversions, balanced insertions/translocations), low‑level mosaicism (<20 %), or rearrangements in repetitive/heterochromatic regions. It cannot identify pure uniparental heterodisomy; it only detects isodisomy, mixed or segmental isodisomy. Suboptimal DNA quality or specimen issues may reduce resolution and lead to erroneous results.
New York Approved
Methodology
Microarray (SNP Array)
Biomarkers
Result Turnaround Time
Not provided.
Related Documents
For more information, please review the documents below
Specimen
Amniotic Fluid
Volume
20 mL
Minimum Volume
20 mL
Container
Sterile Container
Other tests from different labs that may be relevant