17-43067617-T-C

Variant names:

• chr17-43067617-T-C
• rs1555579619
• NM_007294.4:c.5065A>G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PM5

The NM_007294.4(BRCA1):​c.5065A>G​(p.Met1689Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M1689R) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 30)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3 O:1
• Conservation: PhyloP100: 4.79

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a strand (size 3) in uniprot entity BRCA1_HUMAN there are 6 pathogenic changes around while only 1 benign (86%) in NM_007294.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-43067616-A-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.5065A>G	p.Met1689Val	missense_variant	Exon 16 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.5065A>G	p.Met1689Val	missense_variant	Exon 16 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 30

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Jun 16, 2019

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 16, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.M1689V variant (also known as c.5065A>G), located in coding exon 15 of the BRCA1 gene, results from an A to G substitution at nucleotide position 5065. The methionine at codon 1689 is replaced by valine, an amino acid with highly similar properties. A similar alteration at the same codon, p.M1689R (c.5066T>G), has been shown to segregate with disease in a large 3-generation family and lead to a loss-of-function phenotype in both yeast and mammalian transcription assays (Mirkovic N, et al. Cancer Res. 2004 Jun; 64(11):3790-7). This similar alteration has also been classified as likely pathogenic (p>0.9889) by multifactorial analysis, which integrates the following lines of evidence to produce a quantitative likelihood of pathogenicity: in silico prediction models, segregation with disease, tumor characteristics, mutation co-occurrence, and functional assay results (Easton D et al. Am J Hum Genet. 2007;81:873-883; Lindor NM, et al. Hum. Mutat. 2012 Jan; 33(1):8-21). The p.M1689V variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6502 samples (13004 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.0004% (greater than 225000 alleles tested) in our clinical cohort. This amino acid position is 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. -

Hereditary breast ovarian cancer syndrome Uncertain:1

Jun 22, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1689 of the BRCA1 protein (p.Met1689Val). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 481444). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 30209399) indicates that this missense variant is not expected to disrupt BRCA1 function with a negative predictive value of 95%. This variant disrupts the p.Met1689 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 15172985, 17924331, 20516115, 27272900). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. -

Breast-ovarian cancer, familial, susceptibility to, 1 Other:1

-

Brotman Baty Institute, University of Washington

Significance: not provided

Review Status: no classification provided

Collection Method: in vitro

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Benign	0.12	.;T;.;.;T;.;.;.;T;.
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.92	D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.38	D
MetaRNN	Uncertain	0.60	D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.14	T
MutationAssessor	Benign	1.7	.;L;.;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.66	T
PROVEAN	Benign	-2.2	N;N;.;D;.;N;N;D;N;D
REVEL	Uncertain	0.50
Sift	Benign	0.28	T;D;.;T;.;D;T;T;T;T
Sift4G	Uncertain	0.025	D;D;D;D;D;D;D;.;.;D
Polyphen		0.085, 0.78	.;B;.;.;.;.;.;.;P;.
Vest4		0.67
MVP		0.94
MPC		0.12
ClinPred		0.81	D
GERP RS		5.2
Varity_R		0.71
gMVP		0.64

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1555579619; hg19: chr17-41219634;