COBAS targeted mutation analysis
Testing strategy
The laboratory employs two different Roche COBAS kits for targeted mutation analysis based on real time PCR on a COBAS Z480 Analyser:
- COBAS BRAF V600 Mutation Analysis
- COBAS EGFR Mutation Test V2
BRAF V600 Mutation analysis primarily detects the c.1799T>A p.Val600Glu variant associated with response to BRAF inhibitors including Vemurafenib, but shows limited cross reactivity with the p.Val600Asp, p.Val600Arg, and p.Val600Lys variants.
Limit of detection (percentage variant containing DNA in a background of wild-type) has been determined at 5 percent. Differentiation between the different V600 mutations is not possible with this analysis.
The EGFR Mutation Test detects a number of activating variants within the EGFR gene associated with variable responses to the EGFR tyrosine kinase inhibitors. Detected variants include (but are not limited to) p.Leu858Arg, p.Leu861Gln, exon 19 deletions, exon 20 insertions, and the p.Thr790Met resistance mutation.
Limit of detection has been determined at 5 percent. Complete characterisation of exon 19 deletions and exon 20 insertions is not possible, nor will the assay detect all possible variation of this type.
NHSE funded test referrals should be in accordance with the National Genomic Test Directory for cancer and meet eligibility criteria:
National Genomic Test Directory (NHS England)
Target reporting times
14 calendar days from receipt of sample in the laboratory for routine referrals.
Sample requirements and referral information
Please see referral form for referral information and sample requirements.
Requesting specialties
Contact details
Molecular Pathology enquiries: oxford.molecularhaem@nhs.net
Last reviewed:02 August 2021