NM_000059.4:c.740T>C
Variant summary
Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4
The NM_000059.4(BRCA2):c.740T>C(p.Ile247Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,613,786 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/20 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. I247V) has been classified as Likely benign.
Frequency
Consequence
NM_000059.4 missense
Scores
Clinical Significance
Conservation
Publications
- breast-ovarian cancer, familial, susceptibility to, 2Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen
- Fanconi anemia complementation group D1Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, ClinGen, G2P
- pancreatic cancer, susceptibility to, 2Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- sarcomaInheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
- hereditary breast ovarian cancer syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Fanconi anemiaInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- medulloblastomaInheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
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ACMG classification
Our verdict: Likely_benign. The variant received -1 ACMG points.
Variant Effect in Transcripts
ACMG analysis was done for transcript: NM_000059.4. You can select a different transcript below to see updated ACMG assignments.
RefSeq Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| BRCA2 | NM_000059.4 | MANE Select | c.740T>C | p.Ile247Thr | missense | Exon 9 of 27 | NP_000050.3 | ||
| BRCA2 | NM_001432077.1 | c.740T>C | p.Ile247Thr | missense | Exon 9 of 27 | NP_001419006.1 | |||
| BRCA2 | NM_001406720.1 | c.740T>C | p.Ile247Thr | missense | Exon 9 of 27 | NP_001393649.1 |
Ensembl Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| BRCA2 | ENST00000380152.8 | TSL:5 MANE Select | c.740T>C | p.Ile247Thr | missense | Exon 9 of 27 | ENSP00000369497.3 | ||
| BRCA2 | ENST00000544455.6 | TSL:1 | c.740T>C | p.Ile247Thr | missense | Exon 9 of 27 | ENSP00000439902.1 | ||
| BRCA2 | ENST00000530893.7 | TSL:1 | c.371T>C | p.Ile124Thr | missense | Exon 9 of 27 | ENSP00000499438.2 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152216Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000398 AC: 1AN: 250972 AF XY: 0.00000737 show subpopulations
GnomAD4 exome AF: 0.0000157 AC: 23AN: 1461570Hom.: 0 Cov.: 30 AF XY: 0.0000179 AC XY: 13AN XY: 727096 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152216Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1AN XY: 74360 show subpopulations
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 2 Uncertain:3
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com.
This missense variant replaces isoleucine with threonine at codon 247 of the BRCA2 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 1/250972 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.
not provided Uncertain:2
The BRCA2 c.740T>C (p.Ile247Thr) variant has been reported in the published literature in individuals with ovarian cancer (PMID: 34326862 (2021)) and breast cancer (PMID: 33278427 (2021), 33471991 (2021), see also LOVD (http://databases.lovd.nl/shared/genes/BRCA2)). The frequency of this variant in the general population, 0.000004 (1/250972 chromosomes (Genome Aggregation Database, http://gnomad.broadinstitute.org)), is uninformative in the assessment of its pathogenicity. Analysis of this variant using bioinformatics tools for the prediction of the effect of amino acid changes on protein structure and function yielded predictions that this variant is benign. Based on the available information, we are unable to determine the clinical significance of this variant.
Observed in individuals with breast or ovarian cancer (PMID: 34326862, 33278427); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Also known as 968T>C; This variant is associated with the following publications: (PMID: 34326862, 24817641, 23704879, 29884841, 31853058, 32377563, 33278427)
Hereditary cancer-predisposing syndrome Uncertain:2
This missense variant replaces isoleucine with threonine at codon 247 of the BRCA2 protein. Computational prediction suggests that this variant may not impact protein structure and function. 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 1/250972 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.
The p.I247T variant (also known as c.740T>C), located in coding exon 8 of the BRCA2 gene, results from a T to C substitution at nucleotide position 740. The isoleucine at codon 247 is replaced by threonine, an amino acid with similar properties. 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.
Hereditary breast ovarian cancer syndrome Benign:1
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at