# Wild-type (WT)

Source: https://onco.cc/terms/wild-type/  
OnCo record `wild-type` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

The normal, unmutated version of a gene. Saying a tumour is 'RAS wild-type' means its RAS gene is not mutated, which for colorectal cancer means EGFR antibodies can work.

## Summary

Borrowed from genetics, wild-type is the reference sequence against which mutations are defined. It matters when a mutation predicts resistance rather than sensitivity: only RAS/BRAF wild-type colorectal cancers respond to cetuximab or panitumumab; TP53 wild-type tumours can respond to MDM2 inhibitors; unmutated IGHV in CLL predicts shorter remissions with chemoimmunotherapy. Because 'wild-type' depends on what was tested, a tumour can be wild-type on a small panel and mutated on a larger one.

## Fields

- Kind: Term
- Last checked: 2026-09-09
- Also known as: wild type; wildtype; RAS wild-type; KRAS wild-type; BRAF wild-type; TP53 wild-type; TP53-wild-type; EGFR wild-type; unmutated

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Wild_type
- Wikipedia: https://en.wikipedia.org/wiki/Wild_type

## Connected records

- terms: [Driver mutation](https://onco.cc/terms/driver-mutation/), [KRAS mutation subtypes (G12C, G12D, G12V)](https://onco.cc/terms/kras-mutation-subtypes/), [TP53-mutated (p53-abnormal)](https://onco.cc/terms/tp53-mutated/)
- technologies: [Comprehensive genomic profiling](https://onco.cc/technologies/cgp/)
- fronts: [Diagnostics & Biomarkers](https://onco.cc/fronts/diagnostics/)
- cancers: [Colorectal cancer](https://onco.cc/cancers/colorectal/), [Non-small-cell lung cancer](https://onco.cc/cancers/nsclc/), [Pancreatic ductal adenocarcinoma](https://onco.cc/cancers/pancreatic/)
- key papers: [A molecularly annotated platform of patient-derived xenografts identifies HER2 as an effective therapeutic target in cetuximab-resistant colorectal cancer](https://onco.cc/key-papers/paper-bertotti-xenopatients-her2-cetuximab-resistant-colorectal-cancer-discov-2011/), [Clinical sequencing defines the genomic landscape of metastatic colorectal cancer](https://onco.cc/key-papers/paper-yaeger-metastatic-colorectal-genomic-landscape-cancer-cell-2018/), [eNRGy: efficacy of zenocutuzumab in NRG1 fusion-positive cancer](https://onco.cc/key-papers/paper-enrgy-zenocutuzumab-nrg1-fusion-positive-cancer-nejm-2025/), [Heining 2018: NRG1 fusions in KRAS wild-type pancreatic cancer](https://onco.cc/key-papers/paper-heining-nrg1-fusions-kras-wild-type-pancreatic-cancer-discov-2018/), [HER2 overexpression and amplification as a potential therapeutic target in colorectal cancer: analysis of 3256 patients enrolled in the QUASAR, FOCUS and PICCOLO colorectal cancer trials](https://onco.cc/key-papers/paper-richman-her2-amplification-quasar-focus-piccolo-j-pathol-2016/), [Integrated genomic characterization of pancreatic ductal adenocarcinoma](https://onco.cc/key-papers/paper-tcga-pancreatic-integrated-characterisation-cancer-cell-2017/), [Jones 2019: NRG1 gene fusions are recurrent, clinically actionable rearrangements in KRAS wild-type pancreatic ductal adenocarcinoma](https://onco.cc/key-papers/paper-jones-nrg1-fusions-recurrent-actionable-kras-wild-type-pdac-ccr-2019/), [K-ras mutations and benefit from cetuximab in advanced colorectal cancer](https://onco.cc/key-papers/paper-karapetis-kras-cetuximab-colorectal-nejm-2008/), [Molecular biomarkers for the evaluation of colorectal cancer: guideline from ASCP, CAP, AMP and ASCO](https://onco.cc/key-papers/paper-sepulveda-molecular-biomarkers-colorectal-guideline-jco-2017/), [Molecular characterization of KRAS wild-type tumors in patients with pancreatic adenocarcinoma](https://onco.cc/key-papers/paper-philip-kras-wild-type-pancreatic-ccr-2022/), [Panitumumab vs Bevacizumab Added to Standard First-line Chemotherapy and Overall Survival Among Patients With RAS Wild-type, Left-Sided Metastatic Colorectal Cancer: A Randomized Clinical Trial](https://onco.cc/key-papers/paper-paradigm-jama-2023/), [Panitumumab-FOLFOX4 treatment and RAS mutations in colorectal cancer (PRIME)](https://onco.cc/key-papers/paper-douillard-prime-panitumumab-ras-nejm-2013/), [Prognostic and predictive relevance of primary tumor location in patients with RAS wild-type metastatic colorectal cancer: retrospective analyses of the CRYSTAL and FIRE-3 trials](https://onco.cc/key-papers/paper-tejpar-tumour-location-crystal-fire3-jama-oncol-2017/), [Prognostic and predictive value of primary tumour side in patients with RAS wild-type metastatic colorectal cancer treated with chemotherapy and EGFR directed antibodies in six randomized trials](https://onco.cc/key-papers/paper-arnold-primary-tumour-side-ras-wild-type-ann-oncol-2017/), [Using multiplexed assays of oncogenic drivers in lung cancers to select targeted drugs](https://onco.cc/key-papers/paper-kris-lung-cancer-mutation-consortium-jama-2014/)
- targets: [EGFR](https://onco.cc/targets/egfr/), [KRAS](https://onco.cc/targets/kras/), [NRAS](https://onco.cc/targets/nras/)
- biomarkers: [KRAS G12D (and other non-G12C KRAS mutations)](https://onco.cc/biomarkers/kras-g12d/), [RAS wild-type (extended KRAS and NRAS testing)](https://onco.cc/biomarkers/ras-wild-type/)

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JSON: https://onco.cc/api/v1/entities/wild-type.json