17-43106499-C-G

Position:

• chr17-43106499-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_007294.4(BRCA1):​c.169G>C​(p.Gly57Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,122 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: BRCA1 NM_007294.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3 O:1
• Conservation: PhyloP100: 1.38

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 Uncertain_significance. Variant got 4 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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BRCA1	NM_007294.4	c.169G>C	p.Gly57Arg	missense_variant	4/23	ENST00000357654.9	NP_009225.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BRCA1	ENST00000357654.9	c.169G>C	p.Gly57Arg	missense_variant	4/23	1	NM_007294.4	ENSP00000350283	P4

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152122 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 28

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152122 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74312

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000192

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

not provided, no classification provided	in vitro	Brotman Baty Institute, University of Washington	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Mar 10, 2016	- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 19, 2017

The p.G57R variant (also known as c.169G>C), located in coding exon 3 of the BRCA1 gene, results from a G to C substitution at nucleotide position 169. The glycine at codon 57 is replaced by arginine, an amino acid with dissimilar properties. This alteration was found to prevent the interaction between the BRCA1 protein and the E2 ubiquitin conjugating enzyme UbcH5a (Morris JR et al. Hum. Mol. Genet., 2006 Feb;15:599-606). 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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 15, 2023

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. Experimental studies have shown that this missense change does not substantially affect BRCA1 function (PMID: 30209399). 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. ClinVar contains an entry for this variant (Variation ID: 252391). This missense change has been observed in individual(s) with breast cancer (PMID: 19619314). This variant is present in population databases (no rsID available, gnomAD 0.06%). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 57 of the BRCA1 protein (p.Gly57Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.45	.;T;.;.;.;.;T;.;.;T;T;T;T;.
Eigen	Uncertain	0.46
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.94	D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.46	D
MetaRNN	Uncertain	0.61	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.21	D
MutationAssessor	Benign	0.46	N;N;N;N;.;N;.;.;.;.;.;.;.;.
MutationTaster	Benign	0.99	D;D;D;D;D;D;D;D;D;N;N;N;N;N
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-0.45	N;N;N;N;N;N;N;N;N;.;N;N;D;.
REVEL	Uncertain	0.60
Sift	Uncertain	0.0060	D;D;D;D;D;D;D;D;D;.;D;D;D;.
Sift4G	Uncertain	0.027	D;D;D;T;D;T;.;D;D;.;D;D;.;.
Polyphen		1.0, 1.0, 1.0	.;D;.;.;.;D;.;.;D;.;.;.;.;.
Vest4		0.52
MutPred		0.51		Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);.;Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);.;Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);Gain of solvent accessibility (P = 0.0014);.;
MVP		0.92
MPC		0.48
ClinPred		0.92	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.50
gMVP		0.43

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.20		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.20		Position offset: -43

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs879255289; hg19: chr17-41258516;