BRCA1/BRCA2 Genes, Full Gene Analysis, Varies

Casandra

Casandra Test Code MC19494Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID HBOCZCPT Code 81162

BRCA1/BRCA2 Genes, Full Gene Analysis, Varies

Clinical Use

Use

This test is useful for evaluating patients with a personal or family history suggestive of hereditary breast and ovarian cancer (HBOC) syndrome. It aids in establishing a diagnosis of HBOC syndrome, allowing for targeted cancer surveillance based on associated risks. Additionally, it identifies variants within genes known to be associated with increased risk for HBOC syndrome, facilitating predictive testing of at-risk family members and determining therapeutic eligibility for specific cancer treatments, such as poly(ADP-ribose) polymerase inhibitors.

Special Instructions

Testing minors for adult-onset predisposition syndromes is discouraged by genetic associations. For comprehensive hereditary cancer panels including BRCA1 and BRCA2, alternative tests are available, such as BRGYP / Hereditary Breast/Gynecologic Cancer Panel and others. Testing for BRCA1 and BRCA2 genes as part of a customized panel, as well as targeted testing for familial variants, is also available.

Limitations

The test may not detect all types of genomic variants. Next-generation sequencing has limitations such as variable depth of coverage and may not effectively evaluate certain genomic regions, due to homology, high guanine-cytosine content, and repetitive sequences. The test detects 95% of deletions up to 75 base pairs and insertions up to 47 base pairs, but may miss larger delins. Results may be inaccurate in patients with recent transplants or blood transfusions due to donor DNA presence. Single exon resolution might not be achieved in all cases due to technical limitations.

Test Details

New York Approved