chr2-214781506-A-C

Variant names:

• chr2-214781506-A-C
• rs879253930
• NM_000465.4:c.368T>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.368T>G​(p.Leu123Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000275 in 1,454,940 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: BARD1 NM_000465.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:7
• Conservation: PhyloP100: -0.0450

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=0.22034153).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BARD1	NM_000465.4	c.368T>G	p.Leu123Trp	missense_variant	Exon 4 of 11	ENST00000260947.9	NP_000456.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BARD1	ENST00000260947.9	c.368T>G	p.Leu123Trp	missense_variant	Exon 4 of 11	1	NM_000465.4	ENSP00000260947.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000275 AC: 4 AN: 1454940 Hom.: 0 Cov.: 32 AF XY: 0.00000276 AC XY: 2 AN XY: 723978

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000361

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial cancer of breast Uncertain:3

Nov 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with tryptophan, which is neutral and slightly polar, at codon 123 of the BARD1 protein (p.Leu123Trp). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with BARD1-related conditions. ClinVar contains an entry for this variant (Variation ID: 245753). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

Feb 10, 2024

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 12, 2024

St. Jude Molecular Pathology, St. Jude Children's Research Hospital

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The BARD1 c.368T>G (p.Leu123Trp) missense change is absent in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL is inconclusive about a pathogenic or benign effect of this variant on protein function, and to our knowledge functional studies have not been performed. To our knowledge, this variant has not been reported as pathogenic in individuals with BARD1-related disease. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -

not provided Uncertain:2

Jun 26, 2019

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Sep 29, 2024

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The BARD1 c.368T>G (p.Leu123Trp) variant has not been reported in individuals with BARD1-related conditions in the published literature. It also has not been reported in large, multi-ethnic general populations (Genome Aggregation Database, http://gnomad.broadinstitute.org). Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded conflicting predictions that this variant is benign or damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -

Hereditary cancer-predisposing syndrome Uncertain:2

Dec 05, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces leucine with tryptophan at codon 123 of the BARD1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with BARD1-related disorders 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. -

Jun 25, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.L123W variant (also known as c.368T>G), located in coding exon 4 of the BARD1 gene, results from a T to G substitution at nucleotide position 368. The leucine at codon 123 is replaced by tryptophan, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.087
BayesDel_addAF	Benign	-0.066	T
BayesDel_noAF	Benign	-0.33
CADD	Benign	14
DANN	Benign	0.89
DEOGEN2	Benign	0.18	T;.
Eigen	Benign	-0.70
Eigen_PC	Benign	-0.92
FATHMM_MKL	Benign	0.076	N
LIST_S2	Benign	0.50	T;T
M_CAP	Uncertain	0.12	D
MetaRNN	Benign	0.22	T;T
MetaSVM	Benign	-0.49	T
MutationAssessor	Uncertain	2.5	M;.
PrimateAI	Benign	0.25	T
PROVEAN	Benign	-1.6	N;.
REVEL	Uncertain	0.31
Sift	Benign	0.053	T;.
Sift4G	Benign	0.12	T;T
Polyphen		0.99	D;.
Vest4		0.38
MutPred		0.24		Loss of stability (P = 0.0034);.;
MVP		0.68
MPC		0.32
ClinPred		0.69	D
GERP RS		-5.7
Varity_R		0.034
gMVP		0.28

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: rs879253930; hg19: chr2-215646230;