chr2-214781317-C-A

Position:

• chr2-214781317-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_000465.4(BARD1):​c.557G>T​(p.Ser186Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,512 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BARD1 NM_000465.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.0560

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 5 ACMG points.

• PM1: In a modified_residue Phosphoserine (size 0) in uniprot entity BARD1_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BARD1	NM_000465.4	c.557G>T	p.Ser186Ile	missense_variant	4/11	ENST00000260947.9	NP_000456.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BARD1	ENST00000260947.9	c.557G>T	p.Ser186Ile	missense_variant	4/11	1	NM_000465.4	ENSP00000260947	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460512 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 726322

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 27, 2023

The p.S186I variant (also known as c.557G>T), located in coding exon 4 of the BARD1 gene, results from a G to T substitution at nucleotide position 557. The serine at codon 186 is replaced by isoleucine, an amino acid with dissimilar 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. -

Familial cancer of breast Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 16, 2022

This variant has not been reported in the literature in individuals affected with BARD1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 186 of the BARD1 protein (p.Ser186Ile). ClinVar contains an entry for this variant (Variation ID: 961553). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C15"). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.083	T
BayesDel_noAF	Benign	-0.36
CADD	Benign	21
DANN	Benign	0.94
DEOGEN2	Benign	0.28	T;.
Eigen	Benign	-0.94
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.22	N
LIST_S2	Benign	0.75	T;T
M_CAP	Benign	0.070	D
MetaRNN	Benign	0.19	T;T
MetaSVM	Benign	-0.50	T
MutationAssessor	Uncertain	2.3	M;.
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-2.3	N;.
REVEL	Benign	0.26
Sift	Uncertain	0.0040	D;.
Sift4G	Uncertain	0.0020	D;D
Polyphen		0.51	P;.
Vest4		0.27
MutPred		0.14		Loss of phosphorylation at S186 (P = 0.0085);.;
MVP		0.73
MPC		0.20
ClinPred		0.83	D
GERP RS		-3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.18
gMVP		0.27

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.80		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.80		Position offset: -12

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

Publications

LitVar

Other links and lift over

dbSNP: rs1553622620; hg19: chr2-215646041;