KRAS

Chr 12AD

KRas proto-oncogene, GTPase

Also known as: 'C-K-RAS, C-K-RAS, CFC2, K-RAS2A, K-RAS2B, K-RAS4A, K-RAS4B, K-Ras

This gene, a Kirsten ras oncogene homolog from the mammalian ras gene family, encodes a protein that is a member of the small GTPase superfamily. A single amino acid substitution is responsible for an activating mutation. The transforming protein that results is implicated in various malignancies, including lung adenocarcinoma, mucinous adenoma, ductal carcinoma of the pancreas and colorectal carcinoma. Alternative splicing leads to variants encoding two isoforms that differ in the C-terminal region. [provided by RefSeq, Jul 2008]

GeneReviewsOMIMResearchGenerating clinical summary…
GOFmechanismADLOEUF 1.2412 OMIM phenotypes
VCEP Guidelines: RASopathyReleased
View SpecificationsClinGen Panel
Clinical SummaryKRAS
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Gene-Disease Validity (ClinGen)
cardiofaciocutaneous syndrome · ADStrong

Strong evidence — appropriate for clinical testing

3 total gene-disease associations curated

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
96 unique Pathogenic / Likely Pathogenic· 198 VUS of 552 total submissions
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Clinical Trials
12 active or recruiting trials — potential therapeutic options may be available
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GeneReview available — KRAS
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint?
1.24LOEUF
pLI 0.001
Z-score 1.06
OE 0.63 (0.341.24)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
2.32Z-score
OE missense 0.34 (0.260.45)
33 obs / 97.4 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios?
LoF OE?0.63 (0.341.24)
00.351.4
Missense OE?0.34 (0.260.45)
00.61.4
Synonymous OE?0.93
01.21.6
LoF obs/exp: 6 / 9.5Missense obs/exp: 33 / 97.4Syn Z: 0.34
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveKRAS-related cardiofaciocutaneous syndromeGOFAD
definitiveKRAS-related Noonan syndromeGOFAD

This gene — mechanism propensity

DN
0.77top 25%
GOF
0.75top 25%
LOF
0.3842th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function, dominant-negative and loss-of-function). The Badonyi & Marsh model scores dominant-negative highest among its predictions, but genomic evidence (constraint, ClinVar variant spectrum, and literature) most strongly supports gain-of-function. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median · 1 literature citation · 95% of P/LP are missense
DNprediction above median
LOF1 literature citation

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Literature Evidence

GOFActivating germline mutations of KRAS and HRAS cause severe developmental abnormalities leading to Noonan, cardio-facial-cutaneous, and Costello syndrome, but activating germline mutations of NRAS have not been reported.1
LOFHere we report, a syndromic familial case of a 12p duplication encompassing the dosage sensitive gene KRAS, whose phenotype overlapped with rasopathies.2

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.

ClinVar Variant Classifications

552 submitted variants in ClinVar

Classification Summary

Pathogenic38
Likely Pathogenic58
VUS198
Likely Benign177
Benign36
Conflicting26
38
Pathogenic
58
Likely Pathogenic
198
VUS
177
Likely Benign
36
Benign
26
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
38
0
0
38
Likely Pathogenic
1
53
3
1
58
VUS
25
118
44
11
198
Likely Benign
0
5
82
90
177
Benign
0
1
32
3
36
Conflicting
26
Total26215161105533

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

38 pathogenic / likely-pathogenic (of 39) ClinVar copy-number / structural variants overlap KRAS — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →

Protein Context — Lollipop Plot

KRAS · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

Colon AdenocarcinomaRectal Adenocarcinoma

A Clinical Study of Calderasib (MK-1084) With Targeted Therapy and Chemotherapy in People With Colorectal Cancer (MK-1084-012/KANDLELIT-012)

RECRUITING
NCT06997497Phase PHASE3Merck Sharp & Dohme LLCStarted 2025-07-16
CalderasibOxaliplatinLeucovorin/levofolinate calcium
Non Small Cell Lung CancerSmall Cell Lung CarcinomaNUT Carcinoma

Biology of Young Lung Cancer Study: The YOUNG LUNG Study

RECRUITING
NCT05265429Dana-Farber Cancer InstituteStarted 2023-01-01
Data and Specimen Collection
Carcinoma, Non-Small-Cell Lung

A Study of Participants in China With Non-Small-Cell Lung Cancer That is Unable to be Treated With Surgery

ACTIVE NOT RECRUITING
NCT05872763Hoffmann-La RocheStarted 2023-08-11
Acute Myeloid LeukemiaMyelodysplastic Syndrome With Excess Blasts-2

A Study of Gilteritinib Versus Midostaurin in Combination With Induction and Consolidation Therapy Followed by One-year Maintenance in Patients With Newly Diagnosed Acute Myeloid Leukemia or Myelodysplastic Syndromes With Excess Blasts-2 With FLT3 Mutations Eligible for Intensive Chemotherapy

ACTIVE NOT RECRUITING
NCT04027309Phase PHASE3Stichting Hemato-Oncologie voor Volwassenen NederlandStarted 2019-12-20
GilteritinibMidostaurin
Advanced CancerNon Small Cell Lung Cancer

POTENT - Tepotinib in Combination With Pembrolizumab in NSCLC

ACTIVE NOT RECRUITING
NCT05782361Phase PHASE1Institute of Cancer Research, United KingdomStarted 2023-05-03
TepotinibPembrolizumab
KRAS Gene Mutation

Phase 2 Study of TVB-2640 in KRAS Non-Small Cell Lung Carcinomas

ACTIVE NOT RECRUITING
NCT03808558Phase PHASE2David E GerberStarted 2019-09-11
TVB-2640
Osteonecrosis of the Jaw

Local and Systemic Changes in Osteonecrosis of the Jawbone

ENROLLING BY INVITATION
NCT05329558Medical University of GrazStarted 2018-03-01
Pancreas Cancer

ctDNA Assay in Patients With Resectable Pancreatic Cancer

RECRUITING
NCT05052671University of OklahomaStarted 2022-05-25
Advanced Malignant Solid NeoplasmEGFR Gene AmplificationEGFR Gene Mutation

Neratinib and Everolimus, Palbociclib, or Trametinib in Treating Participants With Refractory and Advanced or Metastatic Solid Tumors With EGFR Mutation/Amplification, HER2 Mutation/Amplification, or HER3/4 Mutation or KRAS Mutation

ACTIVE NOT RECRUITING
NCT03065387Phase PHASE1M.D. Anderson Cancer CenterStarted 2017-10-31
EverolimusNeratinibPalbociclib
Metastatic Colorectal Cancer (mCRC)

DHF-20-1839-2: Clinical Performance Study Protocol for Therascreen® KRAS RGQ PCR Kit

RECRUITING
NCT06645236Phase NAQIAGEN Gaithersburg, IncStarted 2023-12-22
therascreen® KRAS RGQ PCR Kit
Prostate Cancer

A Study of Metastases Free Survival With Saruparib vs Placebo Added to a Standard RT/ADT in Men With High-risk Prostate Cancer With a BRCA Mutation

RECRUITING
NCT06952803Phase PHASE3AstraZenecaStarted 2025-08-06
SaruparibPlaceboAbiraterone + Prednisolone/Prednisone
Non Small Cell Lung Cancer Metastatic

First-line Therapy With Nivolumab Plus Ipilimumab in Combination With Chemotherapy for Metatastatic NSCLC (NICReWo Trial)

RECRUITING
NCT07190677Fondazione IRCCS Policlinico San Matteo di PaviaStarted 2025-01-17