17-43094650-T-C

Variant names:

• chr17-43094650-T-C
• rs1555592934
• NM_007294.4:c.881A>G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP6

The NM_007294.4(BRCA1):​c.881A>G​(p.Lys294Arg) 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 1,461,866 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. K294E) has been classified as Likely benign.

• 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:1 B:1
• Conservation: PhyloP100: 1.88
• Publications: 2 publications found

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 Gene-Disease associations (from GenCC):

• breast-ovarian cancer, familial, susceptibility to, 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• Fanconi anemia, complementation group S

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
• pancreatic cancer, susceptibility to, 4

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary breast ovarian cancer syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Fanconi anemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 17-43094650-T-C is Benign according to our data. Variant chr17-43094650-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 531293.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.881A>G	p.Lys294Arg	missense_variant	Exon 10 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.881A>G	p.Lys294Arg	missense_variant	Exon 10 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461866 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727226

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Uncertain:1

Oct 27, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 294 of the BRCA1 protein (p.Lys294Arg). The lysine residue is weakly conserved and there is a small physicochemical difference between lysine and arginine. This variant has not been reported in the literature in individuals with BRCA1-related disease. 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. -

Hereditary cancer-predisposing syndrome Benign:1

Mar 23, 2023

University of Washington Department of Laboratory Medicine, University of Washington

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: curation

Missense variant in a coldspot region where missense variants are very unlikely to be pathogenic (PMID:31911673). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.099
BayesDel_addAF	Pathogenic	0.32	D
BayesDel_noAF	Pathogenic	0.22
CADD	Benign	21
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.49	T;.;.;.;T;T;.;T
Eigen	Uncertain	0.42
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Benign	0.77	T;T;T;T;T;T;T;T
M_CAP	Pathogenic	0.34	D
MetaRNN	Uncertain	0.45	T;T;T;T;T;T;T;T
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	3.2	M;M;.;.;.;.;.;.
PhyloP100		1.9
PrimateAI	Benign	0.33	T
PROVEAN	Uncertain	-2.5	N;D;N;D;.;N;N;N
REVEL	Pathogenic	0.66
Sift	Uncertain	0.0080	D;D;D;D;.;D;D;D
Sift4G	Benign	0.11	T;T;T;T;.;T;.;T
Polyphen		0.70	P;.;.;P;.;.;.;.
Vest4		0.42
MutPred		0.25		Loss of ubiquitination at K294 (P = 0.0047);Loss of ubiquitination at K294 (P = 0.0047);.;Loss of ubiquitination at K294 (P = 0.0047);.;Loss of ubiquitination at K294 (P = 0.0047);.;Loss of ubiquitination at K294 (P = 0.0047);
MVP		0.89
MPC		0.15
ClinPred		0.84	D
GERP RS		3.8
Varity_R		0.13
gMVP		0.092

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

Other links and lift over

dbSNP: rs1555592934; hg19: chr17-41246667;