Maternal Cell Contamination

Test Details

Use

Used to rule out the presence of maternal cell contamination within a fetal specimen to aid in the accurate interpretation of prenatal molecular genetic or cytogenetic results

Special Instructions

If a prenatal specimen (CVS or amniotic fluid) has not already been submitted to Labcorp for other testing, it must now be provided to complete maternal cell contamination (MCC) analysis.

If cultured cells are needed, an additional 7-12 days may be required. Additional culture fee may be included.

Limitations

False positive or negative results may occur for reasons that include genetic variants, blood transfusions, bone marrow transplantation, or erroneous characterization of family relationships. Molecular-based testing is highly accurate, but as in any laboratory test, rare diagnostic errors may occur. Results are provided for identification of maternal cell contamination in the specimen itself, and not for diagnostic purposes.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Methodology

Analysis of short tandem repeat markers by multiplex fluorescent polymerase chain reaction (PCR) and capillary electrophoresis

References

Bacher J, Schumm JM. Development of Highly Polymorphic Pentanucleotide Tandem Repeat Loci with Low Stutter. Promega Corporation Profiles in DNA. 1998;2(2):3-6.
Ensenberger M, Thompson J, Hill B, et al. Developmental validation of the PowerPlex 16 HS System: an improved 16-locus fluorescent STR multiplex. Forensic Sci Int Genet. 2010 Jul;4(4):257-264.20457027
Nagan N, Faulkner NE, Curtis C, Schrijver I, MCC Guidelines Working Group of the Association for Molecular Pathology Clininical Practice Committee. Laboratory guidelines for detection, interpretation, and reporting of maternal cell contamination in prenatal analyses a report of the association for molecular pathology. J Mol Diagn. 2011 Jan;13(1):7-11.21227389

Specimen Requirements

Information on collection, storage, and volume

Specimen

Whole blood or Labcorp buccal swab kit (buccal swab collection kit contains instructions for use of a buccal swab); amniotic fluid; or chorionic villus sample (CVS). (Submission of maternal blood is required for fetal testing.)

Volume

7 mL whole blood or Labcorp buccal swab kit, 10 mL amniotic fluid, or 20 mg CVS

Minimum Volume

3 mL whole blood or two buccal swabs, 5 mL amniotic fluid, or 10 mg CVS

Container

Lavender-top (EDTA) tube or yellow-top (ACD) tube or Labcorp buccal swab kit, sterile plastic conical tube, or two confluent T-25 flasks for fetal testing

Storage Instructions

Maintain specimen at room temperature or refrigerate.

Causes for Rejection

Frozen or hemolyzed specimen; quantity not sufficient for analysis; improper container