chr17-43124076-G-A

Position:

• chr17-43124076-G-A

Variant summary

Our verdict is Benign. Variant got -17 ACMG points: 0P and 17B. BP4_Strong BP6_Very_Strong BP7 BS1

The NM_007294.4(BRCA1):​c.21C>T​(p.Arg7Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000306 in 1,613,436 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★★).

• Frequency:
  • Genomes: 𝑓 0.0015 (1 hom., cov: 32)
  • Exomes 𝑓: 0.00018 (1 hom.)
• Consequence: BRCA1 NM_007294.4 synonymous
• Clinical Significance: Benign reviewed by expert panel B:21 O:1
• Conservation: PhyloP100: -2.72

Genes affected

BRCA1 (HGNC:1100): (BRCA1 DNA repair associated) This gene encodes a 190 kD nuclear phosphoprotein that plays a role in maintaining genomic stability, and it also acts as a tumor suppressor. The BRCA1 gene contains 22 exons spanning about 110 kb of DNA. The encoded protein combines with other tumor suppressors, DNA damage sensors, and signal transducers to form a large multi-subunit protein complex known as the BRCA1-associated genome surveillance complex (BASC). This gene product associates with RNA polymerase II, and through the C-terminal domain, also interacts with histone deacetylase complexes. This protein thus plays a role in transcription, DNA repair of double-stranded breaks, and recombination. Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers. Alternative splicing plays a role in modulating the subcellular localization and physiological function of this gene. Many alternatively spliced transcript variants, some of which are disease-associated mutations, have been described for this gene, but the full-length natures of only some of these variants has been described. A related pseudogene, which is also located on chromosome 17, has been identified. [provided by RefSeq, May 2020]

BRCA1 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -17 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.76).
• BP6: Variant 17-43124076-G-A is Benign according to our data. Variant chr17-43124076-G-A is described in ClinVar as [Benign]. Clinvar id is 136537.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-43124076-G-A is described in Lovd as [Likely_benign]. Variant chr17-43124076-G-A is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=-2.72 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.000177 (259/1461156) while in subpopulation AFR AF= 0.00646 (216/33456). AF 95% confidence interval is 0.00575. There are 1 homozygotes in gnomad4_exome. There are 107 alleles in male gnomad4_exome subpopulation. Median coverage is 30. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.21C>T	p.Arg7Arg	synonymous_variant	2/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.21C>T	p.Arg7Arg	synonymous_variant	2/23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes AF: 0.00154 AC: 235 AN: 152162 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.00548

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000393

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000442 AC: 111 AN: 251058 Hom.: 1 AF XY: 0.000332 AC XY: 45 AN XY: 135680

Gnomad AFR exome AF: 0.00622

Gnomad AMR exome AF: 0.000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000177 AC: 259 AN: 1461156 Hom.: 1 Cov.: 30 AF XY: 0.000147 AC XY: 107 AN XY: 726946

Gnomad4 AFR exome AF: 0.00646

Gnomad4 AMR exome AF: 0.000246

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.000447

GnomAD4 genome AF: 0.00154 AC: 235 AN: 152280 Hom.: 1 Cov.: 32 AF XY: 0.00145 AC XY: 108 AN XY: 74464

Gnomad4 AFR AF: 0.00546

Gnomad4 AMR AF: 0.000392

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000703 Hom.: 0

Bravo AF: 0.00174

ClinVar

Significance: Benign

Submissions summary: Benign:21 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

not specified Benign:4

Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Dec 23, 2014	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 15, 2014	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Oct 20, 2021	- -
Benign, no assertion criteria provided	clinical testing	Clinical Genetics Laboratory, Department of Pathology, Netherlands Cancer Institute	-	- -

not provided Benign:4

Likely benign, no assertion criteria provided	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Nov 16, 2017	- -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Mar 29, 2022	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -

Breast-ovarian cancer, familial, susceptibility to, 1 Benign:3 Other:1

Likely benign, criteria provided, single submitter	literature only	Counsyl	Sep 26, 2014	- -
not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Benign, reviewed by expert panel	curation	Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA)	Jun 29, 2017	Synonymous substitution variant, with low bioinformatic likelihood to alter mRNA splicing (splicing prior 0.02; http://priors.hci.utah.edu/PRIORS/) and frequency 0.0053 (African), derived from ExAC (2014-12-17). -
Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Hereditary cancer-predisposing syndrome Benign:3

Benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 28, 2015	- -
Benign, criteria provided, single submitter	curation	Sema4, Sema4	Sep 29, 2020	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 09, 2014	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Hereditary breast ovarian cancer syndrome Benign:3

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 01, 2024	- -
Benign, criteria provided, single submitter	clinical testing	National Health Laboratory Service, Universitas Academic Hospital and University of the Free State	Apr 19, 2022	- -
Likely benign, criteria provided, single submitter	research	Genetics Program, Instituto Nacional de Cancer	Nov 01, 2021	- -

Breast and/or ovarian cancer Benign:1

Benign, criteria provided, single submitter

clinical testing

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Jan 18, 2017

- -

Malignant tumor of breast Benign:1

Likely benign, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The BRCA1, p.Arg7Arg variant was identified in 25 of 112686 proband chromosomes (frequency: 0.0002) from individuals or families with breast cancer (Fackenthal 2011, Houdayer 2012, Judkins 2005). The variant was also identified in dbSNP (ID: rs149402012) as “other”, Clinvitae database (uncertain significance by EmvClass, likely benign by ClinVar, benign by Invitae), ARUP COSMIC, the ClinVar database (uncertain significance by COG-CHEO, likely benign by Ambry Genetics and Counsyl, benign by GeneDx, Emory Genetics and Invitae), GeneInsight COGR database (uncertain significance by COG-CHEO, likely benign by COG-NYG, benign by LMM), UMD (56X with a “likely neutral” classification). In UMD the variant was identified with a co-occurring pathogenic BRCA1 variant (c.4484G>T, p.Arg1495Met), increasing the likelihood that the p.Arg7Arg variant does not have clinical significance. This variant was identified in the 1000 Genomes Project in 8 of 5000 chromosomes (frequency: 0.002), NHLBI GO Exome Sequencing Project in 22 of 4404 African American alleles, Exome Aggregation Consortium database (August 8, 2016) in 63 (1 homozygous) of 120800 chromosomes (freq. 0.0005) in the following populations: African in 59 of 10322 chromosomes (freq. 0.006), and Latino in 4 of 11516 chromosomes (freq. 0.0003), increasing the likelihood that this may be a low frequency benign variant in certain populations of origin. The p.Arg7Arg variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. In addition, 1 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. In summary, based on the above information, the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -

BRCA1-related disorder Benign:1

Benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Apr 10, 2019

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Familial cancer of breast Benign:1

Benign, criteria provided, single submitter

clinical testing

Baylor Genetics

Feb 23, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.76
CADD	Benign	0.63
DANN	Benign	0.86
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs149402012; hg19: chr17-41276093; COSMIC: COSV58790612; COSMIC: COSV58790612;