2-214728917-C-G

Position:

• chr2-214728917-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000465.4(BARD1):​c.2093G>C​(p.Gly698Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. 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. G698V) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BARD1 NM_000465.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.54

Genes affected

BARD1 (HGNC:952): (BRCA1 associated RING domain 1) This gene encodes a protein which interacts with the N-terminal region of BRCA1. In addition to its ability to bind BRCA1 in vivo and in vitro, it shares homology with the 2 most conserved regions of BRCA1: the N-terminal RING motif and the C-terminal BRCT domain. The RING motif is a cysteine-rich sequence found in a variety of proteins that regulate cell growth, including the products of tumor suppressor genes and dominant protooncogenes. This protein also contains 3 tandem ankyrin repeats. The BARD1/BRCA1 interaction is disrupted by tumorigenic amino acid substitutions in BRCA1, implying that the formation of a stable complex between these proteins may be an essential aspect of BRCA1 tumor suppression. This protein may be the target of oncogenic mutations in breast or ovarian cancer. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.083872765).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BARD1	NM_000465.4	c.2093G>C	p.Gly698Ala	missense_variant	11/11	ENST00000260947.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BARD1	ENST00000260947.9	c.2093G>C	p.Gly698Ala	missense_variant	11/11	1	NM_000465.4	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 02, 2021

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 missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The alanine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with BARD1-related conditions. ClinVar contains an entry for this variant (Variation ID: 924835). This variant is not present in population databases (ExAC no frequency). This sequence change replaces glycine with alanine at codon 698 of the BARD1 protein (p.Gly698Ala). The glycine residue is moderately conserved and there is a small physicochemical difference between glycine and alanine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Nov 20, 2019

This missense variant replaces glycine with alanine at codon 698 of the BARD1 protein. Computational prediction tool suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold ≤0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.060
BayesDel_addAF	Benign	-0.34	T
BayesDel_noAF	Benign	-0.73
CADD	Benign	14
DANN	Benign	0.97
DEOGEN2	Benign	0.23	T;.;.;.;T;.
Eigen	Benign	-0.58
Eigen_PC	Benign	-0.41
FATHMM_MKL	Benign	0.48	N
LIST_S2	Uncertain	0.86	D;D;D;D;D;.
M_CAP	Benign	0.011	T
MetaRNN	Benign	0.084	T;T;T;T;T;T
MetaSVM	Benign	-0.95	T
MutationAssessor	Benign	-0.46	N;.;.;.;.;.
MutationTaster	Benign	0.60	D;N;N
PrimateAI	Benign	0.27	T
PROVEAN	Benign	-2.0	N;.;.;.;.;.
REVEL	Benign	0.077
Sift	Benign	0.72	T;.;.;.;.;.
Sift4G	Benign	0.94	T;T;T;T;T;T
Polyphen		0.0020	B;.;.;.;.;.
Vest4		0.072
MutPred		0.47		Loss of ubiquitination at K693 (P = 0.0734);.;.;.;.;.;
MVP		0.73
MPC		0.081
ClinPred		0.10	T
GERP RS		3.0
Varity_R		0.14
gMVP		0.62

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: rs1553612188; hg19: chr2-215593641;