A need exists for robust and cost-effective assays to detect a single or small set
of actionable point mutations, or a complete set of clinically informative mutant
alleles. Knowledge of these mutations can be used to alert the clinician to a rare
mutation that might necessitate more aggressive clinical monitoring or a personalized
course of treatment. An example is
BRAF, a (proto)oncogene susceptible to either common or rare mutations in codon V600 and
adjacent codons. We report a diagnostic technology that leverages the unique capabilities
of droplet digital PCR to achieve not only accurate and sensitive detection of
BRAF
V600E but also all known somatic point mutations within the
BRAF V600 codon. The simple and inexpensive two-well droplet digital PCR assay uses a
chimeric locked nucleic acid/DNA probe against wild-type
BRAF and a novel wild-type–negative screening paradigm. The assay shows complete diagnostic
accuracy when applied to formalin-fixed, paraffin-embedded tumor specimens from metastatic
colorectal cancer patients deficient for Mut L homologue-1.
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Article Info
Publication History
Published online: January 04, 2016
Accepted:
September 17,
2015
Footnotes
Supported by Genome Canada Strategic Opportunity Fund grant SOF151 and National Sciences and Engineering Research Council of Canada Discovery grant 311796 (both to C.H.).
Disclosures: None declared.
Identification
Copyright
© 2016 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc.
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