Maternal Cell Contamination (MCC) - Saskatoon
Discipline
Overview
Description
Ordering recommendations
-
This test evaluates the possibility of maternal cell contamination (MCC) in fetal specimens.
-
Biological maternal DNA / blood sample are required to be submitted together with fetal sample in order to complete MCC testing.
-
MCC may be ordered to rule out maternal cell contamination of fetal DNA samples that will be sent for further genetic testing.
-
Fetal DNA sources could be from uncultured / cultured amniocytes, products of conception (POC), fetal umbilical cord and cord blood.
-
Fetal parts need to be identified from POC by a pathologist before MCC testing.
Ordering requirements
Specimen Information
Specimen types accepted
- Amniotic fluid
- Peripheral blood
- Tissues, such as products of conception, fetal umbilical cords and pathologist identified fetal parts
Specimen collection container
- Preferred direct amniotic fluid collection container: 2 sterile 15 mL tubes such as Corning or BD
- Preferred collection container for peripheral blood: Lavender (EDTA)
- Preferred collection container: Sterile orange or pink topped Starplex container
Collection procedure
- 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
- If collecting peripheral blood, invert tube several times to mix
Required volume
- Minimum volume for the biological mother: 2 mL blood
- Direct amniotic fluid optimal volume: 15-20 mL divided between two tubes
- Minimum volume for pediatric patient: 1 mL of cord blood
- Approximately 2.5 cm of cord from placental end
- Approximately 0.5 x 0.5 cm of fetal tissue, identified by a pathologist
Transport and stability
- Specimens are to be kept and delivered at room temperature
- Do not freeze specimen or expose to extreme heat
- Do not formalin fix the tissue
- if storing overnight, keep refrigerated at 4-8°C
Rejection criteria
- Mislabelled/unlabelled Specimen
- Incorrect collection tube
- Frozen specimen
- Specimen collected more than 5 days prior to receipt in the laboratory
- Specimen exposed to formalin
- Pathology and Laboratory Medicine Acceptance and Rejection Criteria
Performance
Methodology
-
This test evaluates the possibility of maternal cell contamination (MCC) of fetal DNA sources by concurrently testing and comparing with the biological maternal DNA sample using the YourGene Rapid Aneuploidy detection (RAD) QST*Rplusv2 kit for semi-quantitative assessment with short tandem repeat (STR) markers.
Days/times performed
Availability
-
Specimens are received in the RUH Genomics Laboratory weekdays from 8:00 a.m. to 5:00 p.m.
-
There is a technologist on call Saturday, Sunday and statutory holidays from 8:30 a.m. to 5:00 p.m. for urgent specimens only. This person can be reached through Royal University Hospital Switchboard (306-655-1000)
Maximum laboratory time
Result reporting
-
Turnaround time: 5 business days, after receipt of both the fetal and biological maternal DNA samples
-
Results will be reported as either “No significant MCC detected” or “Significant MCC Detected”.
Specimen retention time
- If DNA banking is requested, the DNA will be extracted and sent to RRPL for storage as their banking policy.
Other information
-
Biological maternal DNA / blood sample needs to be submitted together with fetal sample in order to complete MCC testing
-
Grounds for Rejection:
-
Mislabelled/unlabelled Specimen
-
Incorrect collection tube
-
Frozen specimen
-
Specimen collected more than 5 days prior to receipt in the laboratory
-
Specimen exposed to formalin
-
Pathology and Laboratory Medicine Acceptance and Rejection Criteria
-
Last Updated: April 2, 2024