17-43106487-A-G

Variant names:

• chr17-43106487-A-G
• rs28897672
• NM_007294.4:c.181T>C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_007294.4(BRCA1):​c.181T>C​(p.Cys61Arg) variant causes a missense change. 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C61G) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:6 U:1 O:1
• Conservation: PhyloP100: 5.10

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 Pathogenic. Variant got 18 ACMG points.

• PM1: In a zinc_finger_region RING-type (size 41) in uniprot entity BRCA1_HUMAN there are 65 pathogenic changes around while only 6 benign (92%) 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 chr17-43106487-A-C is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989
• PP5: Variant 17-43106487-A-G is Pathogenic according to our data. Variant chr17-43106487-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 54360.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-43106487-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.181T>C	p.Cys61Arg	missense_variant	Exon 4 of 23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.181T>C	p.Cys61Arg	missense_variant	Exon 4 of 23	1	NM_007294.4	ENSP00000350283.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:6 Uncertain:1 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Nov 29, 2001

Breast Cancer Information Core (BIC) (BRCA1)

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

-

Brotman Baty Institute, University of Washington

Significance: not provided

Review Status: no classification provided

Collection Method: in vitro

- -

Jun 02, 2021

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 02, 2015

Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA), c/o University of Cambridge

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary breast ovarian cancer syndrome Pathogenic:2

Mar 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 61 of the BRCA1 protein (p.Cys61Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with a personal and/or family history of breast and/or ovarian cancer (PMID: 19329713, 25948282, 26757417, 30078507). This variant is also known as 300T>C. ClinVar contains an entry for this variant (Variation ID: 54360). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (PMID: 30209399) indicates that this missense variant is expected to disrupt BRCA1 function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects BRCA1 function (PMID: 22843421, 25823446, 30209399). This variant disrupts the p.Cys61 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 7894493, 9525870, 11278247, 19594371, 19770520, 22172724). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Feb 28, 2021

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: BRCA1 c.181T>C (p.Cys61Arg) results in a non-conservative amino acid change located in the RING domain of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 250754 control chromosomes. c.181T>C has been reported in the literature in multiple individuals affected with Hereditary Breast And Ovarian Cancer Syndrome (example, Rebbeck_2018). These data indicate that the variant is very likely to be associated with disease. At least two publications report somewhat conflicting experimental evidence evaluating an impact on homology directed repair (HDR) capacity (example, Starita_2015, Findlay_2018). The most pronounced variant effect in one study reports a loss of E3 ligase activity, BARD1 binding activity and a predicted loss of homology directed repair (HDR) capacity (Starita_2015). However, a subsequent study by the same authors reports an intermediate HDR activity (Findlay_2018). One clinical diagnostic laboratory and one consortium (CIMBA, captured in Rebbeck_2018) have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All submitters classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided Pathogenic:1

Feb 07, 2018

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Pathogenic:1

Mar 28, 2024

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.C61R variant (also known as c.181T>C), located in coding exon 3 of the BRCA1 gene, results from a T to C substitution at nucleotide position 181. The cysteine at codon 61 is replaced by arginine, an amino acid with highly dissimilar properties. This variant has been observed in multiple individuals with a personal and/or family history that is consistent with BRCA1-related hereditary breast and ovarian cancer syndrome (Al-Mulla F et al. J Clin Pathol, 2009 Apr;62:350-6; Kluska A et al. BMC Med Genomics, 2015 May;8:19; Ng PS et al. Clin Genet, 2016 Oct;90:315-23; Li A et al. Gynecol Oncol, 2018 Oct;151:145-152). One functional study found that this nucleotide substitution to have intermediate function in a high throughput genome editing haploid cell survival assay (Findlay GM et al. Nature, 2018 Oct;562:217-222). Another variant at the same codon, p.C61G (c.181T>G), represents a common mutation in European populations, and has been identified in patients with breast, ovarian, pancreatic, and prostate cancer (Gronwald J et al. J. Med. Genet. 2006 May;43:424-8; Janaviius R. EPMA J. 2010 Sep;1:397-412; Meisel C et al. Arch. Gynecol. Obstet. 2017 May;295:1227-1238; Brand R et al. Cancer. 2018 Sep;124:3520-3527; Ibrahim M et al. BMC Cancer. 2018 02;18:179), and has been shown to be deleterious in functional studies (Towler WI et al. Hum. Mutat. 2013 Mar;34:439-45; Findlay GM et al. Nature. 2018 10;562:217-222). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	.;T;.;.;.;.;D;.;.;T;T;D;D;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.96	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Pathogenic	4.4	H;H;H;H;.;H;.;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-1.4	N;N;N;D;N;N;D;D;N;.;N;D;D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;.;D;D;D;.
Sift4G	Uncertain	0.0060	D;D;D;T;D;D;.;T;D;.;D;D;.;.
Polyphen		0.99, 1.0, 1.0	.;D;.;.;.;D;.;.;D;.;.;.;.;.
Vest4		0.96
MutPred		0.97		Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);.;Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);.;Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);Gain of disorder (P = 0.0336);.;
MVP		1.0
MPC		0.57
ClinPred		1.0	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.99
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.11		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: rs28897672; hg19: chr17-41258504;