BRAF Codon 600 Mutation Detection with Reflex to MLH1 Promoter Methylation

Also known as: BRAF RFLX

Clinical Use

Use

This test evaluates BRAF (NM_004333) exon 15 for hotspot single nucleotide variants (SNVs), multiple nucleotide variants (MNVs), and small insertions/deletions in tumor tissue, with clinical implications in solid tumors including colorectal cancer. If a BRAF V600E mutation is not detected, the test reflexes to MLH1 promoter methylation analysis, aiding in the differentiation between Lynch syndrome–associated and sporadic colorectal cancers and informing diagnosis, prognosis, and therapeutic decision-making ([arupconsult.com](https://www.arupconsult.com/node/23289?utm_source=openai)).

Special Instructions

Not provided.

Limitations

This test does not detect variants outside targeted genomic regions, copy number alterations, translocations, microsatellite instability, tumor mutational burden, deep intronic variants, large indels (>25 bp), or RNA variants. It cannot distinguish somatic from germline variants. Low‑DNA inputs (1–5 ng) may yield suboptimal results and are accepted only with client‑approved disclaimer. Technical limitations include pseudogenes, GC‑rich, repetitive, homologous, or low‑mappability regions, and primer‑overlaps. Variant allele frequency is not reported. Results must be interpreted in broader clinical context ([arupconsult.com](https://www.arupconsult.com/node/23289?utm_source=openai)).

Test Details

Methodology

NGS (Targeted)

Biomarkers

BRAF, MLH1

Gene

SNV/Indel

Mutation • Categorical (e.g., Positive / Negative / Indeterminate)

Result Turnaround Time

Not provided.

Specimen

Tissue (FFPE)

Volume

Not provided

Minimum Volume

Not provided

Container

Block or unstained 5‑micron slides (Min: 5 slides)

Collection Instructions

Formalin‑fixed (10% neutral buffered formalin, not decalcified unless EDTA) paraffin‑embedded tumor tissue ≥ 25% tumor burden; transport block or 8 unstained 5 µm slides (Min: 5). For NY: 10 unstained nonbaked slides + 1 H&E slide