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Identity Testing - MCC Studies, Zygosity

Alternate test name

Maternal Cell Contamination Studies, Zygosity

Lab area
Genome Diagnostics - Molecular Genetics
Method and equipment
STR (short tandem repeat) analysis
Expected turn-around time
Prenatal samples: 2 weeks Pregnancy/STAT: 2-3 weeks Routine: 4-6 week
Specimen type
  • Blood 
  • gDNA
  • cultured amniocytes
  • chorionic villus

For details about specimen requirements, please refer to: Specimen Type & Requirements (PDF).

Specimen requirements
  • Blood: 5-10 mL in EDTA, 0.5 mL in EDTA (neonate); 
  • DNA-minimum 10 ug in 100 uL low TE (pH8.0)

 If sending a prenatal sample, please contact the laboratory prior to sending sample to discuss sample requirements. 

Storage and transportation

Blood, DNA: Room Temperature

For details about specimen requirements, please refer to: Specimen Type and Requirements

Special requirements

Special Instructions for Genome Diagnostics Samples

If sample shipment >48 hours, ship on ice.

Shipping information
The Hospital for Sick Children
Division of Genome Diagnostics
555 University Avenue, Black Wing, Room 3416
Toronto, ON
M5G 1X8
Phone: 416-813-7200 ext. 2
Hours: Monday to Friday, 8 a.m. to 4:30 p.m.
Off hours: Please send to Rapid Response Laboratory, 555 University Avenue, Room 3642
Email Molecular Lab:
Email Cytogenetics:
Background and clinical significance

Individuals can be distinguished from one another by DNA fingerprinting, which compares nine to sixteen variable DNA markers in different regions of the genome. Each person has their own pattern of markers - a DNA ‘fingerprint’. PCR amplification followed by gel electrophoresis allows comparison of these markers from different individuals. This method can be used to determine the biological relationships between family members such as identity and zygosity testing. Determining the relationships between family members can be very important if a genetic cause for a disease is being considered, since the genetic diagnosis of one family member may apply to the other family members as well. DNA fingerprinting can also be used to evaluate the purity of tissue samples obtained for other kinds of tests. Maternal cell contamination of fetal cell samples obtained for prenatal analysis can be assessed in this way, and sample mix-ups or labeling errors can be detected by using DNA fingerprinting to match tissue samples from the same person taken at different times. DNA fingerprinting is also used to distinguish between the X and Y chromosomes for sex determination.

See related information sheets: 

Identity Testing Zygosity Testing

Identity Testing MCC/Fetal Sexing

Disease condition

Maternal Cell Contamination (MCC)

Zygosity Testing

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