chr17-43115728-G-C

Position:

• chr17-43115728-G-C

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The ENST00000357654.9(BRCA1):​c.132C>G​(p.Cys44Trp) variant causes a missense, splice region change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. C44F) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BRCA1 ENST00000357654.9 missense, splice_region
• Scores: Splicing: ADA: 0.9381
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 4.40

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 Pathogenic. Variant got 12 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 6 benign, 17 uncertain in ENST00000357654.9
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-43115729-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 54200.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.989
• PP5: Variant 17-43115728-G-C is Pathogenic according to our data. Variant chr17-43115728-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 647970.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.132C>G	p.Cys44Trp	missense_variant, splice_region_variant	3/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.132C>G	p.Cys44Trp	missense_variant, splice_region_variant	3/23	1	NM_007294.4	ENSP00000350283	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary breast ovarian cancer syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 06, 2019

This variant disrupts the p.Cys44 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19543972, 27083775, 21922593, 25823446, 23633455, 18159056, 25777348, 16267036, 30209399). This suggests that this residue is clinically-significant, and that variants that disrupt this residue are likely to be disease-causing. This variant has not been reported in the literature in individuals with BRCA1-related disease. 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. This variant affects the highly conserved Cys44 residue within the N-terminal RING domain of the BRCA1 protein (PMID: 22843421). This variant has been reported to affect BRCA1 protein function (PMID: 30209399). This variant is not present in population databases (ExAC no frequency). This sequence change replaces cysteine with tryptophan at codon 44 of the BRCA1 protein (p.Cys44Trp). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and tryptophan. -

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

not provided, no classification provided

in vitro

Brotman Baty Institute, University of Washington

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.47	.;T;.;.;.;D;.;T;T;.;T;D;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.96	D;D;D;D;D;D;D;D;D;T;D;D;T
M_CAP	Pathogenic	0.66	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.3	H;H;H;H;H;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.69	T
PROVEAN	Uncertain	-3.4	D;N;N;D;D;D;N;.;N;N;D;D;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;.;D;D;D;D;D
Sift4G	Uncertain	0.0080	D;D;D;D;D;.;D;.;D;.;D;.;.
Polyphen		1.0, 1.0	.;D;.;.;D;.;D;.;.;.;.;.;.
Vest4		0.91
MutPred		0.95		Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);Loss of disorder (P = 0.0272);
MVP		1.0
MPC		0.47
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.98
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.94
dbscSNV1_RF	Benign	0.63
SpliceAI score (max)		0.020		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: rs876658362; hg19: chr17-41267745;