chr17-43082414-T-C

Position:

• chr17-43082414-T-C

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 0P and 13B. BP4_Strong BP6_Very_Strong BP7

The NM_007294.4(BRCA1):​c.4347A>G​(p.Thr1449=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000107 in 1,614,020 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★★). Synonymous variant affecting the same amino acid position (i.e. T1449T) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000059 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00011 (1 hom.)
• Consequence: BRCA1 NM_007294.4 synonymous
• Clinical Significance: Likely benign reviewed by expert panel U:2 B:12
• Conservation: PhyloP100: -0.184

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]

ACMG classification

Verdict is Benign. Variant got -13 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP6: Variant 17-43082414-T-C is Benign according to our data. Variant chr17-43082414-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 55176.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr17-43082414-T-C is described in Lovd as [Benign]. Variant chr17-43082414-T-C is described in Lovd as [Likely_pathogenic]. Variant chr17-43082414-T-C is described in Lovd as [Likely_benign].
• BP7: Synonymous conserved (PhyloP=-0.184 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.4347A>G	p.Thr1449=	synonymous_variant	12/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.4347A>G	p.Thr1449=	synonymous_variant	12/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes AF: 0.0000591 AC: 9 AN: 152212 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00154

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000796 AC: 20 AN: 251220 Hom.: 0 AF XY: 0.0000663 AC XY: 9 AN XY: 135774

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000979

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.000112 AC: 163 AN: 1461690 Hom.: 1 Cov.: 30 AF XY: 0.000106 AC XY: 77 AN XY: 727122

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00401

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome AF: 0.0000591 AC: 9 AN: 152330 Hom.: 0 Cov.: 32 AF XY: 0.0000940 AC XY: 7 AN XY: 74494

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00155

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000567

Asia WGS AF: 0.000866 AC: 3 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Uncertain:2 Benign:12

Revision: reviewed by expert panel

Submissions by phenotype

Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:1 Benign:4

Likely benign, criteria provided, single submitter	clinical testing	Counsyl	Dec 21, 2017	- -
Likely benign, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Dec 13, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Likely 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 result in a splicing aberration (Splicing prior probability 0.02; http://priors.hci.utah.edu/PRIORS/). -
Benign, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA1)	Dec 27, 2004	- -

Hereditary cancer-predisposing syndrome Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 18, 2015	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 21, 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. -
Likely benign, criteria provided, single submitter	curation	Sema4, Sema4	Jun 19, 2021	- -

not specified Benign:2

Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	May 21, 2018	Variant summary: BRCA1 c.4347A>G alters a non-conserved nucleotide resulting in a synonymous change. 5/5 computational tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The observed variant frequency within East Asian control individuals in the gnomAD database (0.001) is close to the estimated maximal expected allele frequency for a pathogenic variant in BRCA1 causing Hereditary Breast and Ovarian Cancer phenotype (0.001), suggesting that the variant is a benign polymorphism found primarily in populations of East Asian origin. Moreover, in certain East Asian subpopulations the variant was observed with an even higher occurrence, e.g. in the Japanese control population it occurred with a frequency of 0.0087 (HGVD), strongly suggesting a benign role for the variant. c.4347A>G has been reported in the literature in individuals affected with Hereditary Breast and Ovarian Cancer (Han 2006, Judkins 2005, Kim 2006, Lee 2003, Hwang 2017). However, in several of these publications the authors listed the variant of interest as a polymorphism. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as benign/likely benign. Based on the evidence outlined above, the variant was classified as benign. -
Benign, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	May 15, 2019	- -

Malignant tumor of breast Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The BRCA1 p.Thr1449= variant was identified in 7 of 3724 proband chromosomes (frequency: 0.002) from Korean and Malaysian individuals or families with breast cancer, sporadic or unselected for family history, and was not identified in 334 control chromosomes from healthy individuals (Han 2006, Kim 2006, Lee 2003). The variant was also identified in the following databases: dbSNP (ID: rs80356840) as “With other allele”, in ClinVar (likely benign, reviewed by an expert panel 2017; submitters: benign by BIC, likely benign by ENIGMA, Invitae, Ambry Genetics and GeneDx), in Clinvitae (4x), and BIC Database (1x, with no clinical importance, classification pending), and was not identified in the COGR, Cosmic, MutDB, LOVD 3.0, UMD-LSDB, ARUP Laboratories, or the Zhejiang Colon Cancer Database. The variant was identified in control databases in 22 of 277016 chromosomes at a frequency of 0.00008 (Genome Aggregation Database Feb 27, 2017). It was observed in the following populations: “Other” in 1 of 6464 chromosomes (freq: 0.0002), East Asian in 20 of 18866 chromosomes (freq: 0.001), and South Asian in 1 of 30758 chromosomes (freq: 0.00003); it was not observed in the African, Latino, European Non-Finnish, Ashkenazi Jewish, and Finnish populations. The p.Thr1449= 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. The variant occurs 11 nucleotides from the 3’ end of exon 11 and 2 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. This variant is classified as a variant of uncertain significance. -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Aug 10, 2020

This variant is associated with the following publications: (PMID: 28179634, 17100994, 16949048, 12872263, 16267036, 28392550, 30702160, 28692638) -

BRCA1-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Oct 27, 2021

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

Hereditary breast ovarian cancer syndrome Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 24, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	3.7
DANN	Benign	0.74

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs80356840; hg19: chr17-41234431;