chr17-43093249-T-G

Position:

• chr17-43093249-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_007294.4(BRCA1):​c.2282A>C​(p.Glu761Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,770 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6 B:1
• Conservation: PhyloP100: 0.392

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
• BP4: Computational evidence support a benign effect (MetaRNN=0.27290773).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.2282A>C	p.Glu761Ala	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.2282A>C	p.Glu761Ala	missense_variant	10/23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461770 Hom.: 0 Cov.: 44 AF XY: 0.00000138 AC XY: 1 AN XY: 727184

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2 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	Ambry Genetics	Apr 30, 2023	The p.E761A variant (also known as c.2282A>C), located in coding exon 9 of the BRCA1 gene, results from an A to C substitution at nucleotide position 2282. The glutamic acid at codon 761 is replaced by alanine, an amino acid with dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 06, 2019	- -

Breast-ovarian cancer, familial, susceptibility to, 1 Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Breast Cancer Information Core (BIC) (BRCA1)	Nov 25, 2004	- -
Uncertain significance, no assertion criteria provided	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	May 05, 2023	a variant of uncertain significance was detected in the BRCA1 gene (c.2282A>C).The p.Glu761Alavariant (also known as c.2282A>C), located in coding exon 10 (NM_007300.3) of the BRCA1 gene, results from an A to C substitution at nucleotide position 2282. The glutamic acid at codon 761 is replaced by alanine, an amino acid with dissimilar properties. This amino acid position is not well conserved (PhyloP=0.39) .This variant does not have a gnomAD exomes entry, but its locus is covered in gnomAD exomes. ClinVar contains an entry for this variant (Variation ID: 54520). In addition, this alteration is predicted to be tolerated by in silico analysis.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 provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Oct 21, 2020

Not observed in large population cohorts (Lek 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Hereditary breast ovarian cancer syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 15, 2023

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. ClinVar contains an entry for this variant (Variation ID: 54520). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with alanine, which is neutral and non-polar, at codon 761 of the BRCA1 protein (p.Glu761Ala). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.096	D
BayesDel_noAF	Benign	-0.10
CADD	Benign	13
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.49	T;.;.;.;T
Eigen	Benign	-0.42
Eigen_PC	Benign	-0.55
FATHMM_MKL	Benign	0.098	N
LIST_S2	Benign	0.84	T;T;T;T;T
M_CAP	Uncertain	0.20	D
MetaRNN	Benign	0.27	T;T;T;T;T
MetaSVM	Benign	-0.41	T
MutationAssessor	Uncertain	2.6	M;M;.;.;.
PrimateAI	Benign	0.26	T
PROVEAN	Pathogenic	-4.7	D;D;D;D;.
REVEL	Uncertain	0.45
Sift	Benign	0.044	D;D;D;D;.
Sift4G	Uncertain	0.053	T;T;T;T;.
Polyphen		0.22	B;.;.;D;.
Vest4		0.34
MutPred		0.30		Loss of solvent accessibility (P = 0.0769);Loss of solvent accessibility (P = 0.0769);.;Loss of solvent accessibility (P = 0.0769);.;
MVP		0.63
MPC		0.35
ClinPred		0.19	T
GERP RS		1.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.11
gMVP		0.14

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: rs80356869; hg19: chr17-41245266;