BRCA1

Chr 17ADAR

BRCA1 DNA repair associated

Also known as: BRCAI, BRCC1, BROVCA1, FANCS, IRIS, PNCA4, PPP1R53, PSCP

The BRCA1 protein functions as an E3 ubiquitin ligase that facilitates DNA repair by forming polyubiquitin chains and coordinating cellular responses to DNA damage through homologous recombination. Heterozygous mutations cause autosomal dominant familial breast-ovarian cancer syndrome and increase susceptibility to pancreatic cancer, while biallelic mutations result in autosomal recessive Fanconi anemia complementation group S. The pathogenic mechanism involves loss of DNA repair capacity leading to genomic instability and increased cancer risk in the heterozygous state, or severe DNA repair deficiency causing bone marrow failure and developmental abnormalities in the homozygous state.

OMIMResearchSummary from RefSeq, OMIM, UniProt
LOFmechanismAD/ARLOEUF 0.923 OMIM phenotypes
Clinical SummaryBRCA1
🧬
Gene-Disease Validity (ClinGen)
BRCA1-related cancer predisposition · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

2 total gene-disease associations curated

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
💊
Clinical Trials
12 active or recruiting trials — potential therapeutic options may be available

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.92LOEUF
pLI 0.000
Z-score 2.16
OE 0.73 (0.590.92)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
0.58Z-score
OE missense 0.95 (0.901.00)
891 obs / 941.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.73 (0.590.92)
00.351.4
Missense OE0.95 (0.901.00)
00.61.4
Synonymous OE0.96
01.21.6
LoF obs/exp: 55 / 75.2Missense obs/exp: 891 / 941.3Syn Z: 0.51
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
strongBRCA1-related Fanconi anemiaLOFAR
definitiveBRCA1-related cancerLOFAD
DN
0.6356th %ile
GOF
0.4085th %ile
LOF
0.56top 25%

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

DNprediction above median · 1 literature citation
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

DNAll of these treatments were found to induce substantial levels of apoptosis in the presence of wild-type BRCA1, whereas dominant negative BRCA1 truncation mutants diminished the apoptotic response.PMID:10938285
LOFVan der Merwe et al. (2020) used MLPA and NGS to evaluate 744 patients with breast cancer or ovarian cancer in a South African cohort. 7 individuals were found to have large genomic rearrangements of BRCA1 (1.1% of total patients).PMID:32375709

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

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

BRCA1 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

Breast CancerGenetic Susceptibility

ScreenIng of Genetic Susceptibility Genes for Breast Cancer Patients in CHinese communiTies

RECRUITING
NCT04265937Fudan UniversityStarted 2019-07-01
Advanced Solid TumorsEwing SarcomaHepatocellular Carcinoma (HCC)

A Phase 1/1B Study of ST-01156, a Small Molecule RBM39 Degrader, in Patients With Advanced Solid Malignancies

RECRUITING
NCT07197554Phase PHASE1SEED Therapeutics, Inc.Started 2025-12-01
ST-01156
Breast Cancer

Assessing Clinical Features and Outcome of Breast Cancer in PALB2 Mutation Carriers: the Palbreast Study

RECRUITING
NCT06403904Azienda Ospedaliero-Universitaria di ModenaStarted 2023-10-02
Malignant Neoplasm of BreastBreast Cancer

Comprehensive Analysis of Predictors of the Treatment With Pembrolizumab and Olaparib in Patients With Unresectable or Metastatic HER2 Negative Breast Cancer and a Deleterious Germline Mutation or a Homologous Recombination Deficiency (COMPRENDO

ACTIVE NOT RECRUITING
NCT05033756Phase PHASE2Institut fuer FrauengesundheitStarted 2022-07-30
Pembrolizumab Injection [Keytruda]Olaparib Oral Tablet [Lynparza]
Pancreatic CancerPancreatic Ductal AdenocarcinomaPDAC

A Prospective Registry for Patients at High-Risk for Pancreatic Cancer

RECRUITING
NCT06151223Mayo ClinicStarted 2021-07-13
Bio-specimen Collection: BloodBio-specimen Collection: Pancreatic JuiceMRI
BRCA1 Gene MutationBRCA2 Gene MutationLocally Advanced Solid Neoplasm

Pembrolizumab in Treating Participants With Metastatic, Recurrent or Locally Advanced Cancer and Genomic Instability

ACTIVE NOT RECRUITING
NCT03428802Phase PHASE2Rutgers, The State University of New JerseyStarted 2018-03-08
Laboratory Biomarker AnalysisPembrolizumab
Breast CancerPALB2-Mutated Breast CarcinomaHER2-negative Breast Cancer

Phase Ib Study of Axatilimab in Combination With Olaparib in BRCA1/2 and PALB2- Associated Metastatic HER2-negative Breast Cancer

RECRUITING
NCT06488378Phase PHASE1Dana-Farber Cancer InstituteStarted 2024-08-13
AxatilimabOlaparib
Metastatic Solid TumorBRCA1 MutationBRCA2 Mutation

Combination Therapy in Cancers With Mutations in DNA Repair Genes

RECRUITING
NCT05694715Phase PHASE1University of California, San FranciscoStarted 2023-05-23
NiraparibIrinotecan
Lymphoma, Non-HodgkinMultiple MyelomaAdvanced Solid Tumors

Canadian Profiling and Targeted Agent Utilization Trial (CAPTUR)

RECRUITING
NCT03297606Phase PHASE2Canadian Cancer Trials GroupStarted 2018-03-23
OlaparibDasatinibNivolumab plus Ipilimumab
Prostate Cancer

PROMISE Registry: A Prostate Cancer Registry of Outcomes and Germline Mutations for Improved Survival and Treatment Effectiveness

RECRUITING
NCT04995198Prostate Cancer Clinical Trials ConsortiumStarted 2021-05-03
Pancreatic Acinar Cell CarcinomaPancreatic AdenocarcinomaPancreatic Adenosquamous Carcinoma

The PLATINUM Trial: Optimizing Chemotherapy for the Second-Line Treatment of Metastatic BRCA1/2 or PALB2-Associated Metastatic Pancreatic Cancer

ACTIVE NOT RECRUITING
NCT06115499Phase PHASE2, PHASE3Alliance for Clinical Trials in OncologyStarted 2024-08-13
Nab paclitaxelGemcitabineCisplatin
Solid TumorAdvanced Solid TumorMetastatic Cancer

KPMNG Study of MOlecular Profiling Guided Therapy Based on Genomic Alterations in Advanced Solid Tumors II

RECRUITING
NCT05525858Seoul National University Bundang HospitalStarted 2022-09-28
AlectinibAtezolizumabErlotinib
Clinical Literature
Open Research Assistant →