rs1060501302

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_000465.4(BARD1):​c.166A>G​(p.Ile56Val) 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 1,460,282 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 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. I56S) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

BARD1
NM_000465.4 missense

Scores

1
17

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.80

Publications

1 publications found
Variant links:
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]
BARD1 Gene-Disease associations (from GenCC):
  • breast cancer
    Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
  • hereditary breast carcinoma
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
  • familial ovarian cancer
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • hereditary nonpolyposis colon cancer
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 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 2 benign, 42 uncertain in NM_000465.4
PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.19809392).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000465.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
BARD1
NM_000465.4
MANE Select
c.166A>Gp.Ile56Val
missense
Exon 2 of 11NP_000456.2
BARD1
NM_001282545.2
c.166A>Gp.Ile56Val
missense
Exon 2 of 7NP_001269474.1
BARD1
NM_001282549.2
c.166A>Gp.Ile56Val
missense
Exon 2 of 5NP_001269478.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
BARD1
ENST00000260947.9
TSL:1 MANE Select
c.166A>Gp.Ile56Val
missense
Exon 2 of 11ENSP00000260947.4
BARD1
ENST00000613706.5
TSL:1
c.166A>Gp.Ile56Val
missense
Exon 2 of 11ENSP00000484976.2
BARD1
ENST00000619009.5
TSL:1
c.166A>Gp.Ile56Val
missense
Exon 2 of 5ENSP00000482293.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460282
Hom.:
0
Cov.:
29
AF XY:
0.00
AC XY:
0
AN XY:
726598
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33416
American (AMR)
AF:
0.00
AC:
0
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39602
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86236
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1110726
Other (OTH)
AF:
0.00
AC:
0
AN:
60314
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.225
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Familial cancer of breast Uncertain:1
Oct 28, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 56 of the BARD1 protein (p.Ile56Val). 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: 406781). 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 valine 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.

Hereditary cancer-predisposing syndrome Uncertain:1
Dec 21, 2018
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I56V variant (also known as c.166A>G), located in coding exon 2 of the BARD1 gene, results from an A to G substitution at nucleotide position 166. The isoleucine at codon 56 is replaced by valine, an amino acid with highly similar properties. This amino acid position is 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.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.10
BayesDel_addAF
Benign
-0.047
T
BayesDel_noAF
Benign
-0.31
CADD
Benign
10
DANN
Benign
0.84
DEOGEN2
Benign
0.049
T
Eigen
Benign
-0.54
Eigen_PC
Benign
-0.38
FATHMM_MKL
Benign
0.66
D
LIST_S2
Benign
0.71
T
M_CAP
Benign
0.044
D
MetaRNN
Benign
0.20
T
MetaSVM
Benign
-0.47
T
MutationAssessor
Benign
0.56
N
PhyloP100
1.8
PrimateAI
Uncertain
0.60
T
PROVEAN
Benign
-0.45
N
REVEL
Benign
0.14
Sift
Benign
0.26
T
Sift4G
Benign
0.21
T
Polyphen
0.0010
B
Vest4
0.15
MutPred
0.21
Gain of MoRF binding (P = 0.1331)
MVP
0.86
MPC
0.065
ClinPred
0.24
T
GERP RS
4.5
Varity_R
0.11
gMVP
0.22
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs1060501302; hg19: chr2-215661834; API