Test Overview
Relative-quantitative PCR uses TaqMan probe and primers to amplify and detect a targeted DNA segment so that the copy number of the target can be calculated in comparison to a calibrator DNA sample. The relative copy number of the target region is calculated based on a calibrator copy number of "two" for most genomic regions.
This Chromosomal Microarray (CMA) analysis uses the Illumina Global Diversity Array with Cytogenetics (GDAC) content. The GDAC uses approximately 1.8M markers for high exon coverage in targeted regions to detect various types and sizes of structural genomic variation in the human genome. Patient DNA is isolated, linearly amplified, enzymatically fragmented, and hybridized to array probes. Each hybridized array probe is extended with tagged terminating nucleotides. The extended probes are stained, and the array is washed, scanned, and the results are analyzed and interpreted. Only clinically significant copy number variants (CNVs) and/or regions of homozygosity (ROHs) will be reported.
Confirmation of a clinical or a suspected diagnosis of DiGeorge syndrome in a patient. Tier 1 of this panel includes rqPCR using multiple TaqMan probes within the most common region deleted in the 22q11.2 deletion. Tier 2, Chromosomal Microarray (CMA), is run simultaneously.
Interpretive report provided.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Test Details
Tier 1 (DIGP1)(rqPCR): 7 days; Tier 2 (DIGP2)(microarray): 28 days.
- Chromosomal Microarray (CMA)
- DIGP2
- Velocardiofacial Syndrome (VCFS)
- CATCH 22
- SNPM1
- DIGP1
- rqPCR for 22q11.2 deletion
Specimen Requirements
Collect blood specimen in a EDTA lavender top tube. Send it within 24 hours if stored at room temperature or within 5 days if stored refrigerated.
Fill out a MLabs Molecular test requisition (or place an e-order if applicable):
https://mlabs.umich.edu/media/166
Fill out a Clinical History Form for Insurance Prior Authorization (include all required documentation indicated at the bottom of this form):
https://mlabs.umich.edu/sites/default/files/2020-08/file/mlab11618clini…
Fill out a UMHS Request and Consent for Genetic Testing form:
https://mlabs.umich.edu/sites/default/files/2023-04/file/germline-conse…
Michigan State law requires the ordering provider to obtaining informed consent from the patient prior to prognostic or predictive genetic testing. Contact a MLabs Client Services Center at 800-862-7284 to request paper copies or to setup a client account.
Additional Information
The DiGeorge Panel (order code DIGP1) includes rqPCR (Tier 1), and Chromosomal Microarray (CMA) (order code DIGP2) is performed (Tier 2). By ordering this test the clinician acknowledges that both tests will be performed and billed at a separate additional charge.
Most insurance carriers require prior authorization for genetic testing. Testing will not begin until insurance prior authorization is received by the laboratory or it is confirmed that prior authorization is not required. The ordering health care provider can obtain the prior authorization or request the laboratory to submit it. To obtain BCN prior authorization call Joint Venture Hospital Laboratories (JVHL) at 800-445-4979; for all other insurances, contact the plan directly. By ordering this test the clinician acknowledges that informed consent, https://mlabs.umich.edu/sites/default/files/2023-04/file/germline-conse…, has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes medical geneticist interpretation of results billed as a separate additional charge. This test is not available without interpretation.