NM_007294.4:c.4643C>T
Variant summary
Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBP6
The NM_007294.4(BRCA1):c.4643C>T(p.Thr1548Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000372 in 1,613,914 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T1548T) has been classified as Likely benign.
Frequency
Consequence
NM_007294.4 missense
Scores
Clinical Significance
Conservation
Publications
- breast-ovarian cancer, familial, susceptibility to, 1Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
- Fanconi anemia, complementation group SInheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
- pancreatic cancer, susceptibility to, 4Inheritance: 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
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ACMG classification
Our verdict: Likely_benign. The variant received -3 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152154Hom.: 0 Cov.: 31 show subpopulations
GnomAD2 exomes AF: 0.00000796 AC: 2AN: 251282 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 0.00000342 AC: 5AN: 1461760Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1AN XY: 727180 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152154Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1AN XY: 74326 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Breast-ovarian cancer, familial, susceptibility to, 1 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This submission and the accompanying classification are no longer maintained by the submitter.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. -
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a variant of uncertain significance was detected in the BRCA1 gene (c.4706C>T) results in a non-conservative amino acid change in the encoded protein sequence. This variant is present in population databases (rs273900737, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 55249) by five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. In-silico tools predict a benign effect of the variant on 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. -
not specified Uncertain:1Benign:1
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Variant summary: BRCA1 c.4643C>T (p.Thr1548Met) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 251282 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.4643C>T has not been reported in the literature in individuals affected with Breast or Ovarian Cancer outside of references to the BIC database (e.g. Woods_2016). These reports do not provide unequivocal conclusions about association of the variant with Hereditary Breast And Ovarian Cancer Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function. These results showed no damaging effect of this variant on transcriptional activity (Woods_2016, Fernandes_2019). Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. Three laboratories classified the variant as uncertain significance and two as likely benign. Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
Hereditary cancer-predisposing syndrome Benign:2
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. -
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not provided Uncertain:1
This variant is denoted BRCA1 c.4643C>T at the cDNA level, p.Thr1548Met (T1548M) at the protein level, and results in the change of a Threonine to a Methionine (ACG>ATG). Using alternate nomenclature this variant would be defined as BRCA1 4762C>T. BRCA1 Thr1548Met has not, to our knowledge, been published in the literature as pathogenic or benign. This variant was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. Since Threonine and Methionine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. BRCA1 Thr1548Met occurs at a position that is not conserved and is located in a region of interaction with multiple proteins (Cantor 2001, Yarden 1999). In silico analyses predict that this variant is unlikely to alter protein structure or function. Based on the currently available information, we consider BRCA1 Thr1548Met to be a variant of uncertain significance. -
Hereditary breast ovarian cancer syndrome Uncertain:1
This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1548 of the BRCA1 protein (p.Thr1548Met). This variant is present in population databases (rs273900737, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with BRCA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 55249). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt BRCA1 protein function with a negative predictive value of 95%. Experimental studies have shown that this missense change does not substantially affect BRCA1 function (PMID: 28781887, 30765603). 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. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at