rs771852699
Variant summary
Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBS2_Supporting
The NM_000465.4(BARD1):c.2155A>G(p.Thr719Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,614,096 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T719I) has been classified as Uncertain significance.
Frequency
Consequence
NM_000465.4 missense
Scores
Clinical Significance
Conservation
Publications
- breast cancerInheritance: AD Classification: DEFINITIVE Submitted by: G2P
- hereditary breast carcinomaInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
- familial ovarian cancerInheritance: AD Classification: LIMITED Submitted by: ClinGen
- hereditary nonpolyposis colon cancerInheritance: AD Classification: LIMITED Submitted by: ClinGen
Genome browser will be placed here
ACMG classification
Our verdict: Likely_benign. The variant received -3 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| BARD1 | NM_000465.4 | c.2155A>G | p.Thr719Ala | missense_variant | Exon 11 of 11 | ENST00000260947.9 | NP_000456.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| BARD1 | ENST00000260947.9 | c.2155A>G | p.Thr719Ala | missense_variant | Exon 11 of 11 | 1 | NM_000465.4 | ENSP00000260947.4 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152210Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.0000278 AC: 7AN: 251364 AF XY: 0.0000294 show subpopulations
GnomAD4 exome AF: 0.00000479 AC: 7AN: 1461886Hom.: 1 Cov.: 32 AF XY: 0.00000550 AC XY: 4AN XY: 727244 show subpopulations
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152210Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74370 show subpopulations ⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
Age Distribution
ClinVar
Submissions by phenotype
not provided Uncertain:2
In silico analysis supports that this missense variant does not alter protein structure/function; Published functional studies demonstrate similar protein production and reduced homology-directed repair (HDR) activity relative to wildtype (Adamovich et al., 2019); This variant is associated with the following publications: (PMID: 25233892, 28135145, 17550235, 26898890, 33471991, 30925164, 35264596) -
- -
Familial cancer of breast Uncertain:2
This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 719 of the BARD1 protein (p.Thr719Ala). This variant is present in population databases (rs771852699, gnomAD 0.02%). This missense change has been observed in individual(s) with colorectal cancer (PMID: 28135145). ClinVar contains an entry for this variant (Variation ID: 406754). 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. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on BARD1 function (PMID: 30925164). 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:1Benign:1
This missense variant replaces threonine with alanine at codon 719 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). A functional study has shown that this variant protein leads to homology directed repair activity similar to the wild-type protein in a cell-based assay (PMID: 30925164). This variant has been reported in an individual affected with colorectal cancer, who carried a causative variant in the MLH1 gene (PMID: 28135145). This variant has been identified in 7/251364 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. -
This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
not specified Uncertain:1
- -
Malignant tumor of breast Uncertain:1
The BARD1 p.Thr719Ala variant was identified in 1 of 2116 proband chromosomes (frequency: 0.0005) from individuals or families with colorectal cancer (Yurgelun 2017). In this proband, the variant co-occurred with a pathogenic MLH1 variant (c.2195_2198dup, p.H733Qfs*14). The variant was also identified in dbSNP (ID: rs771852699) “With Uncertain significance allele” and ClinVar (classified as uncertain significance by Invitae, Color, Prevention Genetics, and two other submitters). The variant was identified in control databases in 7 of 246128 chromosomes (1 homozygous) at a frequency of 0.00003 (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Other in 1 of 5482 chromosomes (freq: 0.0002) and Latino in 6 (1 homozygous) of 33580 chromosomes (freq: 0.0002); it was not observed in the African, European, Ashkenazi Jewish, East Asian, Finnish, or South Asian populations. The p.Thr719 residue is conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information, the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at