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Chromosomal Microarray (CMA) – Saskatoon

Discipline

Genetics and Genomics

Overview

Description

Ordering recommendation
  • Chromosomal Microarray (CMA) is used to detect copy number variants (large deletion or duplication) in the genome.
  • The Division of Medical Genetics is able to order this test
    • The physicians who have been granted approval by the Division of Medical Genetics, such as Pediatricians are pre-approved to order this 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
  • DNA may also be extracted from peripheral blood at RRPL for testing
  • NOTE: If Patient is from Regina/Southern Saskatchewan please seek requisition and referred out testing to British Columbia
Ordering Requirements

Alias

  • Chromosomal Microarray 

  • CMA

Specimen Information

Specimen types accepted

  • Peripheral blood/whole blood

  • Skin or other tissue
  • Amniotic fluid

Specimen collection container

Preferred collection container:

Collection procedure

  • ​Invert tube several times to mix

  • Specimen must be accompanied by a completed test requisition, signed by physician
  • Failure to include relevant patient information may result in test results being delayed or discontinued

Required volume

  • Optimal Volume: 4 – 7 mL
  • Minimum Volume for adult: 2 mL blood
  • Minimum Volume for Pediatric patient: 1 mL of peripheral blood or cord blood

(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.)

  • 0.5 cm x 0.5 cm tissue specimen
  • Amniotic fluid: 2x 15 mL tubes

Transport and stability

  • Ship specimens at ambient temperature

  • Specimens may be stored at 2 - 8°C

Rejection criteria

Testing Information

Relevant clinical history

Patient History

 

  • Developmental Delay/MR                             
  • Prenatal growth retardation
  • Postnatal growth anomalies
  • Dysmorphic features
  • Congenital anomalies
  • Autism Spectrum disorders
  • Neurological issues
  • Any other relevant indications
  • Please refer to the requisition for details

Performance

Methodology

  • Chromosomal Microarray (CMA) detects gains or losses of genomic regions, including aneuploidy. 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.  Copy number gains and losses that represent common variants in studies of healthy control populations will not be reported. 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.

Days/times performed

Availability

  • Specimens accepted Monday to Friday, 8:00 am to 5:00 pm in the RUH Genomics Laboratory
  • Current referred out Location: Alberta Children’s Hospital, Alberta Precision Laboratories, Calgary, AB
  • Specimens are sent to Calgary within 7 days of receipt

Maximum laboratory time

Results reporting

  • ​Turnaround time for routine test is 28 days

  • Turnaround time for STAT is 14 days
  • Consult with RUH Genomics lab regarding reflex testing. Reflex testing after abnormal microarray results could require FISH by cytogenetics and/or qPCR by molecular methods for confirmation of array results and/or follow-up for family members.

Specimen retention time

  • DNA is banked on all microarray specimens. Banked DNA will be stored at RRPL as their banking policy.

Last Updated: April 11, 2024