Ordering Recommendation
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- Ordering of this test is restricted to physicians who have been granted approval by the department of Medical Genetics
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Specimen Requirements
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| Type | - Peripheral blood/whole blood
- Skin or other tissue
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| Container | - Preferred Collection Container:
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Collection Procedure
| - Invert tube several times to mix
- Specimen must be accompanied by a completed test requisition
- Failure to include relevant patient information may result in test results being delayed or discontinued
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| Required Volume | - Optimal Volume: 4 – 7 mL
- Minimum Volume: 2 mL
(Submitting the minimum volume makes it impossible to repeat the test or perform confirmatory/reflex testing. In some situations, a minimum volume may require a second collection.) - Pediatric Volume: 2 mL of peripheral blood or cord blood
- 0.5 cm x 0.5 cm skin specimen
- Blocks are accepted as received
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| Stability/Storage | - Ship specimens at ambient temperature
- Specimens may be stored at 2 – 8 ° C
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| Grounds for Rejection | |
Testing Information |
| Availability | - Specimens accepted Monday to Friday, 8:00 am to 5:00 pm in the Cytogenetics Laboratory
- STAT tests are sent to Calgary within 7 days of specimen receipt
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| Testing Site | - Alberta Children’s Hospital, Calgary, AB
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| Results Reporting | - Turnaround time for routine test is 28 days
- Turnaround time for STAT is 14 days
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Reflex Testing
| - Reflex testing after abnormal microarray results will require either FISH by cytogenetics or qPCR by molecular methods for confirmation of array results and/or follow-up for family members
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| Methodology | - DNA is banked on all microarray specimens. Banked DNA will be stored at RRPL. Should further genetic testing be needed, please see Genetic Testing/Molecular Genetics
- Infinium CyoSNP-850K v1.2 bead chip
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Clinical Interpretation
| - The array CGH technology detects gains or losses of targeted DNA sequences including aneuploidy, with high accuracy and sensitivity. It does not detect gains or losses of non-tested sequences, balanced chromosomal rearrangements such as balanced translocations or balanced inversions, point mutations, polyploidy or abnormalities of repetitive sequences and it does not reliably detect mosaicism. Failure to detect a copy number alteration at any locus does not rule out the diagnosis since disorders represented on the array can be caused by other genetic mechanisms
- Anomaly designation follows the most recent edition of the International System for Human Cytogenetic Nomenclature
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Specimen Retention
| - Banked DNA is retained for 50 years
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| Alternate Test Names | |
| Additional Comments | - Specimens are batched and shipped to Calgary on Wednesdays; STAT specimens are shipped on other days if necessary
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| SHR LIS Test Code | - PB, MG (For Lab Use Only)
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Testing Ordering Requirements |
| Preferred Specimen Collection | - Selective Test Centre at RUH or on ward
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Forms Required
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Clearance Required
| - Pediatricians are pre-approved to order microarray testing
- if the requisition is incomplete or the test is ordered by a physician who is not approved, DNA will be extracted and sent to RRPL for banking until testing can proceed
- If you require any other genetic test refer to Genetic testing/Molecular genetics for ordering information
- If planning to request testing or if the specimen has already been collected, DNA banking can be requested until approval can be obtained from Medical Genetics
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Patient History |
Relevant Clinical History
| - Developmental Delay/MR
- Prenatal growth retardation
- Postnatal growth anomalies
- Dysmorphic features
- Congenital anomalies
- Neurological issues
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