2-214767478-T-C

Variant names:

• chr2-214767478-T-C
• rs781268123
• NM_000465.4:c.1568+4A>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000465.4(BARD1):​c.1568+4A>G variant causes a splice region, intron change. The variant allele was found at a frequency of 0.00000274 in 1,460,286 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. 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 splice_region, intron
• Scores: Splicing: ADA: 0.9997
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.13
• Publications: 1 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BARD1	NM_000465.4	c.1568+4A>G		splice_region_variant, intron_variant	Intron 6 of 10	ENST00000260947.9	NP_000456.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BARD1	ENST00000260947.9	c.1568+4A>G		splice_region_variant, intron_variant	Intron 6 of 10	1	NM_000465.4	ENSP00000260947.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000797 AC: 2 AN: 251092 AF XY: 0.0000147

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460286 Hom.: 0 Cov.: 34 AF XY: 0.00000413 AC XY: 3 AN XY: 726556

African (AFR) AF: 0.00 AC: 0 AN: 33436

American (AMR) AF: 0.00 AC: 0 AN: 44708

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.0000464 AC: 4 AN: 86212

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53386

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110662

Other (OTH) AF: 0.00 AC: 0 AN: 60322

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial cancer of breast Uncertain:1

Feb 04, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 6 of the BARD1 gene. It does not directly change the encoded amino acid sequence of the BARD1 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs781268123, gnomAD 0.006%). 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. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 574307). This variant has not been reported in the literature in individuals affected with BARD1-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.18
CADD	Uncertain	25
DANN	Uncertain	0.98
PhyloP100		7.1
Mutation Taster		=5/95	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.96
SpliceAI score (max)		0.24		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.24		Position offset: 0

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

Other links and lift over

dbSNP: rs781268123; hg19: chr2-215632202;