17-43049164-C-G

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Moderate PP5_Moderate

The NM_007294.4(BRCA1):c.5363G>C(p.Gly1788Ala) 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. G1788D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:3 O:1
• Conservation: PhyloP100: 4.31

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 10 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 17 uncertain 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 chr17-43049164-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 37660.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.935
• PP5: Variant 17-43049164-C-G is Pathogenic according to our data. Variant chr17-43049164-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 531438.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BRCA1	NM_007294.4	c.5363G>C	p.Gly1788Ala	missense_variant	21/23	ENST00000357654.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BRCA1	ENST00000357654.9	c.5363G>C	p.Gly1788Ala	missense_variant	21/23	1	NM_007294.4	P4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Likely pathogenic, no assertion criteria provided	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	May 05, 2023	A likely pathogenic variant was detected in this sample. This sequence change replaces glycine with alanine at codon 1809 of the BRCA1 protein (p.Gly1809Ala). The glycine residue is highly conserved and there is a small physicochemical difference between glycine and alanine. This variant is not present in population databases (gnomAD). ClinVar contains an entry for this variant (Variation ID: 531438). This variant has been reported to affect BRCA1 protein function (PMID: 11016938, 30209399). This variant disrupts the p.Gly1809 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 26689913, 17924331, 18418466, 9796975, 21990134, 27272900, 20516115). 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. This variant was confirmed by Sanger Sequencing . -
not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Likely pathogenic, no assertion criteria provided	clinical testing	Biochemical Molecular Genetic Laboratory, King Abdulaziz Medical City	Oct 11, 2020	- -

Hereditary breast ovarian cancer syndrome Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

Aug 16, 2022

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 disrupts the p.Gly1788 amino acid residue in BRCA1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9796975, 17924331, 18418466, 20516115, 21990134, 26689913, 27272900). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Experimental studies have shown that this missense change affects BRCA1 function (PMID: 11016938, 30209399). Advanced modeling of experimental studies (such as gene expression, population dynamics, functional pathways, and cell-cycle effects in cell culture) performed at Invitae indicates that this missense variant is expected to disrupt BRCA1 protein function. ClinVar contains an entry for this variant (Variation ID: 531438). 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 glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 1788 of the BRCA1 protein (p.Gly1788Ala). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.65
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.53
Cadd	Uncertain	24
Dann	Uncertain	1.0
Eigen	Uncertain	0.64
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.97	D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;N;N
PrimateAI	Uncertain	0.51	T
PROVEAN	Pathogenic	-4.7	D;N;.;.;.;.;N;D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0040	D;D;.;.;.;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D
Polyphen		0.34, 1.0	.;B;.;.;.;D;.;.
Vest4		0.90
MVP		0.99
MPC		0.26
ClinPred		0.98	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.81
gMVP		0.84

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: rs80357069; hg19: chr17-41201181;