17-43094051-G-C

Position:

• chr17-43094051-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP6

The NM_007294.4(BRCA1):​c.1480C>G​(p.Gln494Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 2.51

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 17-43094051-G-C is Benign according to our data. Variant chr17-43094051-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 918686.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.1480C>G	p.Gln494Glu	missense_variant	10/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.1480C>G	p.Gln494Glu	missense_variant	10/23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Sep 23, 2019	This missense variant replaces glutamine with glutamic acid at codon 494 of the BRCA1 protein. Computational prediction tool is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Likely benign, criteria provided, single submitter	curation	University of Washington Department of Laboratory Medicine, University of Washington	Mar 23, 2023	Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 26, 2021

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt BRCA1 protein function. This variant has not been reported in the literature in individuals with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 918686). This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamine with glutamic acid at codon 494 of the BRCA1 protein (p.Gln494Glu). The glutamine residue is moderately conserved and there is a small physicochemical difference between glutamine and glutamic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.069
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Benign	18
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.53	D;.;.;.;T;T;.
Eigen	Benign	0.090
Eigen_PC	Benign	-0.10
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Uncertain	0.89	D;D;D;D;D;D;D
M_CAP	Uncertain	0.27	D
MetaRNN	Uncertain	0.46	T;T;T;T;T;T;T
MetaSVM	Uncertain	0.29	D
MutationAssessor	Pathogenic	3.5	M;M;.;.;.;.;.
PrimateAI	Benign	0.22	T
PROVEAN	Uncertain	-2.6	D;D;D;D;.;D;D
REVEL	Uncertain	0.58
Sift	Uncertain	0.011	D;D;D;D;.;D;D
Sift4G	Benign	0.42	T;T;T;T;.;T;.
Polyphen		0.93	P;.;.;P;.;.;.
Vest4		0.41
MutPred		0.49		Loss of sheet (P = 0.0142);Loss of sheet (P = 0.0142);.;Loss of sheet (P = 0.0142);.;Loss of sheet (P = 0.0142);.;
MVP		0.92
MPC		0.18
ClinPred		0.28	T
GERP RS		3.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.20
gMVP		0.048

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: rs80357010; hg19: chr17-41246068;