Laboratory Test Information Guide

Details for Breast Cancer (BRCA1 and BRCA2 Screening)

Test Name: Breast Cancer (BRCA1 and BRCA2 Screening)
Alternate Name(s): Proband
Laboratory: Molecular Diagnostics
Specimen Type: Whole blood-4 mL Lavender EDTA top Vacutainer tube
For specific volumes see Collection Information.
Collection Information: Known Familial mutations: 2 x 4 mL tubes
Unknown mutations: 5 x 4 mL tubes
Ashekenazi Jewish Patients: 2 x 4 mL tubes
French Canadian Patients: 2 x 4 mL tubes

Blood samples must be maintained at room temperature.
Test Schedule: As Required
Monday - Friday
0800 - 1630 h
Turnaround time from when specimen
is received in testing laboratory:
Unknown mutation: 4 months/Known Familial: 2 months
Reference Range: See report
Effective Date:  
Revised Date: 2016-03-21
Critical Value: N/A
Interpretive Comments: A subset (5-10%) of breast / ovarian cancers are familial, and a predisposition to develop malignancy in these tissues has been found to segregate with (autosomal dominant) mutations in either the BRCA1 gene (Chr.17) or the BRCA2 gene (Chr.13). BRCA1 mutations occur in about one half of all kindreds with familial breast cancer, but in a much higher proportion in kindreds with both breast and ovarian cancer. Mutations of this gene are associated with a very high risk of breast cancer (<85% by age 80 yrs.) and a 40-60% lifetime risk for ovarian cancer. A large majority (>80%)of disease causing mutations in either of these two genes cause a premature termination of protein translation and may be screened for by an in-vitro protein truncation assay. Many of the mutations are small insertions or deletions that cause a reading frame shift, and may be rapidly screened for by heteroduplex analysis.
Special Processing:  
Comments: For more information click on:

Method of Analysis: Multiplex Ligation-dependent Probe Amplification (MLPA)
Direct Sequence analysis of the entire coding region
Critical Information Required: Pedigree required.
Storage & Shipment: Must be received in testing laboratory within 48 hours of collection, shipped at room temperature by courier/overnight delivery.
System Codes: 
Referred To:  

Questions? Comments? Contact Laura Gopaul