CMA - Targeted and Limited Karyotype - Prenatal - CVS
Use
CMA - Targeted utilizes array-based comparative genomic hybridization (aCGH) with 180K oligonucleotides designed to perform copy number analysis and detect uniparental disomy (UPD) across specific chromosomes. This prenatal test greatly assists patients who require detection of deletion/duplication syndromes associated with fetal abnormalities. While it proficiently identifies significant genomic gains and losses, it has limitations and does not discern low-level mosaicism, balanced translocations, inversions, or point mutations, ensuring clinical relevance in the scope of prenatal genetic evaluations. This test targets individuals with previous adverse pregnancy experiences, abnormal ultrasound findings, or higher risks due to maternal age, contributing valuable genetic insights.
Special Instructions
Parental blood samples are crucial for the test. Maternal cell contamination studies will be performed in all cases where maternal blood is provided. In cases requiring parental studies, they will be conducted automatically to clarify fetal results. If specific conditions are met, parental studies may be available for a fee, including conditions related to autosomal recessive disorders and X-linked recessive disorders. Testing for absence of heterozygosity (AOH) will be communicated to the client along with recommendations for further testing if necessary, ensuring comprehensive prenatal care.
Limitations
The CMA - Targeted test has specific limitations concerning reporting on certain genomic changes: gains and losses under 1000 kb without relevant genes, gains less than 500 kb but associated with genes of unknown clinical significance, certain known genomic regions, and those linked to adult-onset disorders sans available treatments will remain unreported. While the CMA can effectively identify medically actionable findings for select genes, it does not support a diagnosis on its own and is subject to parental confirmation in relevant cases.
Methodology
Chromosomal / Cytogenetics (FISH)
Biomarkers
Result Turnaround Time
7-10 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (Fresh)
Volume
15+ mg
Minimum Volume
N/A
Container
sterile tissue culture media
Collection Instructions
Collect in sterile tissue culture media. Ship the sample at room temperature to the laboratory by overnight express.
Patient Preparation
N/A
Storage Instructions
Specimen cannot be frozen.
Causes for Rejection
Specimen must arrive within 48 hrs of sample date.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | N/A |
| Refrigerated | N/A |
| Frozen | N/A |
