ERBB2

Chr 17

erb-b2 receptor tyrosine kinase 2

Also known as: CD340, HER-2, HER-2/neu, HER2, MLN 19, MLN-19, NEU, NGL

This gene encodes a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases. This protein has no ligand binding domain of its own and therefore cannot bind growth factors. However, it does bind tightly to other ligand-bound EGF receptor family members to form a heterodimer, stabilizing ligand binding and enhancing kinase-mediated activation of downstream signalling pathways, such as those involving mitogen-activated protein kinase and phosphatidylinositol-3 kinase. Allelic variations at amino acid positions 654 and 655 of isoform a (positions 624 and 625 of isoform b) have been reported, with the most common allele, Ile654/Ile655, shown here. Amplification and/or overexpression of this gene has been reported in numerous cancers, including breast and ovarian tumors. Alternative splicing results in several additional transcript variants, some encoding different isoforms and others that have not been fully characterized. [provided by RefSeq, Jul 2008]

GeneReviewsResearchGenerating clinical summary…
MultiplemechanismLOEUF 0.40
Clinical SummaryERBB2
Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.27) despite low pLI — interpret in context.
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Clinical Trials
12 active or recruiting trials — potential therapeutic options may be available
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GeneReview available — ERBB2
Authoritative clinical overview · Recommended first read
Open GeneReview ↗
Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Missense constrained — critical functional residues
LoF Constraint?
0.40LOEUF
pLI 0.006
Z-score 5.57
OE 0.27 (0.180.40)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint?
3.25Z-score
OE missense 0.67 (0.620.72)
510 obs / 762.5 exp
Constrained

Highly missense-constrained (top ~0.1%)

Observed / Expected Ratios?
LoF OE?0.27 (0.180.40)
00.351.4
Missense OE?0.67 (0.620.72)
00.61.4
Synonymous OE?0.99
01.21.6
LoF obs/exp: 18 / 67.3Missense obs/exp: 510 / 762.5Syn Z: 0.15

This gene — mechanism propensity

DN
0.7325th %ile
GOF
0.88top 5%
LOF
0.2679th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median
DNprediction above median

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.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

ERBB2 · 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

Stage I Breast CancerStage II Breast CancerStage III Breast Cancer

Niraparib + Dostarlimab In BRCA Mutated Breast Cancer

ACTIVE NOT RECRUITING
NCT04584255Phase PHASE2Dana-Farber Cancer InstituteStarted 2020-12-18
NiraparibDostarlimab
Metastatic Solid TumorAdvanced Cancer

High Definition Medicine for Solid Tumors Oncology

RECRUITING
NCT06590506Centro Nacional de Investigaciones Oncologicas CARLOS IIIStarted 2023-03-02
Wearable
Breast Cancer

Identification of HER2-Positive Breast Cancer Molecular Characterization and Subtypes

NOT YET RECRUITING
NCT07187752Phase NAShandong Cancer Hospital and InstituteStarted 2025-09-30
TrastuzumabPertuzumabChemotherapy
Breast Cancer

Prospective Study of the Prosigna Assay on Neoadjuvant Clinical Decision-making in Women With HR+/Her2- Breast Cancer

ACTIVE NOT RECRUITING
NCT03749421Dana-Farber Cancer InstituteStarted 2019-03-21
Prosigna PAM-50 assay
Metastatic Colorectal Adenocarcinoma

CAPRI 2 GOIM Study: Investigate the Efficacy and Safety of a Bio-marker Driven Cetuximab-based Treatment Regimen

ACTIVE NOT RECRUITING
NCT05312398Phase PHASE2University of Campania Luigi VanvitelliStarted 2021-07-15
CetuximabFOLFIRIFOLFOX regimen
Breast Cancer

Preoperative Fulvestrant With or Without Enzalutamide in ER+/Her2- Breast Cancer

ACTIVE NOT RECRUITING
NCT02955394Phase PHASE2University of Colorado, DenverStarted 2017-09-21
EnzalutamideFulvestrant
Bilateral Breast CarcinomaHER2-Negative Breast CarcinomaLocalized Breast Carcinoma

Testing the Addition of an Anti-cancer Drug, Berzosertib, to the Usual Treatment (Radiation Therapy) for Chemotherapy-Resistant Triple-Negative and Estrogen and/or Progesterone Receptor Positive, HER2 Negative Breast Cancer

ACTIVE NOT RECRUITING
NCT04052555Phase PHASE1National Cancer Institute (NCI)Started 2020-09-24
BerzosertibBiospecimen CollectionQuality-of-Life Assessment
Melanoma (Skin Cancer)HER2-low Hormone Receptor Positive Breast Cancer

Study of AMXT 1501 and DFMO in Combination With Standard Therapies in Advanced Solid Tumors

RECRUITING
NCT07287917Phase PHASE1, PHASE2Aminex Therapeutics, Inc.Started 2026-01-26
AMXT 1501 DicaprateDFMOFulvestrant
Breast CancerProstate Cancer

African Cancer Genome: GMD

RECRUITING
NCT05754658Fox Chase Cancer CenterStarted 2022-11-28
Standard of CareStandard of Care
Lung Adenocarcinoma

PHOENIX: QL1706 Plus Chemotherapy and Bevacizumab in AGA-Resistant, PD-L1 ≥50% Non-Squamous NSCLC

NOT YET RECRUITING
NCT07416058Phase PHASE2Guangdong Association of Clinical TrialsStarted 2026-01-31
QL1706 (bispecific antibody targeting PD-1 and CLTA-4)
Anatomic Stage I Breast Cancer AJCC v8Anatomic Stage II Breast Cancer AJCC v8Anatomic Stage III Breast Cancer AJCC v8

Additional Support Program Via Text Messaging and Telephone-Based Counseling for Breast Cancer Patients Receiving Hormonal Therapy

ACTIVE NOT RECRUITING
NCT04379570Phase PHASE3Alliance for Clinical Trials in OncologyStarted 2021-02-15
Educational InterventionText Message-based Navigation InterventionMotivational Interviewing
Hormone Receptor Positive HER-2 Negative Breast Cancer

Impact of Endocrine Therapy, Menstrual Cycle, PAM50, Ki67 on Treatment Decisions in HR+ and HER2- Breast Cancer

RECRUITING
NCT05878314University Hospital TuebingenStarted 2023-04-25