rs1403432043

chr2-214769303-G-Achr2-214769303-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1 PM2 BP4_Moderate

The NM_000465.4(BARD1):c.1324C>T(p.Pro442Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,568 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 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. P442L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: BARD1 NM_000465.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 0.0500

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 2 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 uncertain in NM_000465.4
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.10811114).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BARD1	NM_000465.4	c.1324C>T	p.Pro442Ser	missense_variant	5/11	ENST00000260947.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BARD1	ENST00000260947.9	c.1324C>T	p.Pro442Ser	missense_variant	5/11	1	NM_000465.4	P2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251166 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460568 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726684

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Aug 08, 2022	This missense variant replaces proline with serine at codon 442 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 hereditary cancer in the literature. This variant has been identified in 1/251166 chromosomes 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 25, 2023	The p.P442S variant (also known as c.1324C>T), located in coding exon 5 of the BARD1 gene, results from a C to T substitution at nucleotide position 1324. The proline at codon 442 is replaced by serine, an amino acid with similar properties. This variant was reported in 0/60,466 breast cancer cases and in 1/53,461 controls (Dorling et al. N Engl J Med. 2021 02;384:428-439). This amino acid position is not well 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. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Feb 21, 2023

This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 442 of the BARD1 protein (p.Pro442Ser). This variant is present in population databases (no rsID available, gnomAD 0.0009%). 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: 482806). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.095
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.46
Cadd	Benign	8.2
Dann	Benign	0.57
DEOGEN2	Benign	0.028	T;.
Eigen	Benign	-0.97
Eigen_PC	Benign	-0.95
FATHMM_MKL	Benign	0.082	N
LIST_S2	Benign	0.65	T;T
M_CAP	Benign	0.0061	T
MetaRNN	Benign	0.11	T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.55	N;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.36	T
PROVEAN	Benign	-0.87	N;.
REVEL	Benign	0.017
Sift	Benign	0.41	T;.
Sift4G	Benign	0.61	T;T
Polyphen		0.0030	B;.
Vest4		0.23
MutPred		0.43		Loss of methylation at K438 (P = 0.1438);.;
MVP		0.66
MPC		0.077
ClinPred		0.031	T
GERP RS		1.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.099
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: rs1403432043; hg19: chr2-215634027;