17-43094144-T-C

Position:

• chr17-43094144-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 6P and 1B. PM2 PM5 PP3_Moderate BP6

The NM_007294.4(BRCA1):​c.1387A>G​(p.Lys463Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K463G?) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1 O:1
• Conservation: PhyloP100: 3.40

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 Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-43094144-T-CC is described in ClinVar as [Pathogenic]. Clinvar id is 125497.Status of the report is no_assertion_criteria_provided, 0 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.896
• BP6: Variant 17-43094144-T-C is Benign according to our data. Variant chr17-43094144-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 431211.We mark this variant Likely_benign, oryginal submissions are: {not_provided=1, Likely_benign=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.1387A>G	p.Lys463Glu	missense_variant	10/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.1387A>G	p.Lys463Glu	missense_variant	10/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3 Benign:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

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). -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 11, 2021	This missense variant replaces lysine with glutamic acid at codon 463 of the BRCA1 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in cis with BRCA1 c.1390_1391insG in two hereditary breast and ovarian cancer families (PMID: 11933205). The two in cis variants, c.1387A>G and c.1390_1391insG, may be described together as 1506del4ins5 or c.1387_1390delinsGAAAG (ClinVar variation ID: 54234). 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. -

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.Lys463Glu variant was identified in the literature in two Canadian families of aboriginal descent with breast and ovarian cancer, both with the same BRCA1 alterations (1510insG, 1506A>G). The variant was identified in ClinVar (classified as uncertain significance by CORG). The variant was not identified in dbSNP, LOVD 3.0, or UMD-LSDB, databases. The variant was not identified in the following control databases: the Exome Aggregation Consortium (August 8th 2016), or the Genome Aggregation Database (Feb 27, 2017). The p.Lys463 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. 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. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 17, 2023

This sequence change replaces lysine, which is basic and polar, with glutamic acid, which is acidic and polar, at codon 463 of the BRCA1 protein (p.Lys463Glu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with hereditary breast and/or ovarian cancer (PMID: 11933205). This variant is also known as c.1506A>G. ClinVar contains an entry for this variant (Variation ID: 431211). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on BRCA1 protein function. 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. -

not specified Other:1

not provided, no classification provided

research

Research Molecular Genetics Laboratory, Women's College Hospital, University of Toronto

Dec 17, 2015

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.55
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.46
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D;.;.;.;T;T;.;.;T
Eigen	Uncertain	0.65
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.89	D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.68	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.2	D
MutationAssessor	Pathogenic	3.6	H;H;.;.;.;.;.;.;.
MutationTaster	Benign	0.74	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Benign	0.40	T
PROVEAN	Uncertain	-3.9	D;D;D;D;.;D;D;D;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;D;D;D;.;D;D;D;D
Sift4G	Benign	0.16	T;T;T;T;.;T;.;D;D
Polyphen		1.0	D;.;.;D;.;.;.;.;.
Vest4		0.60
MutPred		0.65		Gain of helix (P = 0.0034);Gain of helix (P = 0.0034);.;Gain of helix (P = 0.0034);.;Gain of helix (P = 0.0034);.;.;Gain of helix (P = 0.0034);
MVP		0.96
MPC		0.53
ClinPred		0.98	D
GERP RS		4.4
Varity_R		0.74
gMVP		0.19

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: rs1135401844; hg19: chr17-41246161;