5-112837891-C-T
Variant summary
Our verdict is Uncertain significance. The variant received 0 ACMG points: 0P and 0B.
The NM_000038.6(APC):c.2297C>T(p.Ala766Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000991 in 1,613,966 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. A766T) has been classified as Uncertain significance.
Frequency
Consequence
NM_000038.6 missense
Scores
Clinical Significance
Conservation
Publications
- classic or attenuated familial adenomatous polyposisInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- desmoid tumorInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp
- familial adenomatous polyposis 1Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
- gastric adenocarcinoma and proximal polyposis of the stomachInheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
- sarcomaInheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
- APC-related attenuated familial adenomatous polyposisInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Turcot syndrome with polyposisInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Cenani-Lenz syndactyly syndromeInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Uncertain_significance. The variant received 0 ACMG points.
Transcripts
RefSeq
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| APC | ENST00000257430.9 | c.2297C>T | p.Ala766Val | missense_variant | Exon 16 of 16 | 5 | NM_000038.6 | ENSP00000257430.4 | ||
| ENSG00000258864 | ENST00000520401.1 | n.228+8919C>T | intron_variant | Intron 3 of 7 | 3 | ENSP00000454861.1 |
Frequencies
GnomAD3 genomes AF: 0.0000329 AC: 5AN: 152172Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000798 AC: 2AN: 250728 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 0.00000752 AC: 11AN: 1461794Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5AN XY: 727196 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000329 AC: 5AN: 152172Hom.: 0 Cov.: 32 AF XY: 0.0000538 AC XY: 4AN XY: 74336 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Familial adenomatous polyposis 1 Uncertain:4Benign:1
- -
This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -
The APC c.2297C>T (p.Ala766Val) missense change has a maximum subpopulation frequency of 0.0040% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL is inconclusive about a pathogenic or benign effect of this variant on protein function, and to our knowledge functional studies have not been performed. To our knowledge, this variant has not been reported in individuals with APC-related familial adenomatous polyposis. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -
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. -
- -
not provided Uncertain:3
- -
The APC c.2297C>T (p.Ala766Val) variant has not been reported in individuals with APC-related conditions in the published literature. The frequency of this variant in the general population, 0.000014 (4/282134 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 damaging. Based on the available information, we are unable to determine the clinical significance of this variant. -
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Observed in individuals undergoing exome sequencing in a population-based study (PMID: 22703879); This variant is associated with the following publications: (PMID: 22703879, 18199528, 27600092) -
Hereditary cancer-predisposing syndrome Uncertain:3
- -
This missense variant replaces alanine with valine at codon 766 of the APC 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 APC-related disorders in the literature. This variant has been identified in 4/282134 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.A766V variant (also known as c.2297C>T), located in coding exon 15 of the APC gene, results from a C to T substitution at nucleotide position 2297. The alanine at codon 766 is replaced by valine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
not specified Uncertain:1
Variant summary: APC c.2297C>T (p.Ala766Val) results in a non-conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 1.2e-05 in 251872 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2297C>T has been observed in at least one individual affected with a Peutz-Jeghers phenotype without evidence of causality (example: Gaddam et al., Am J Gastroenterology 113():p S956, 2018). These report does not provide unequivocal conclusions about association of the variant with Familial Adenomatous Polyposis. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (Gaddam_2018; PMID: 22703879). ClinVar contains an entry for this variant (Variation ID: 41522). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Classic or attenuated familial adenomatous polyposis Uncertain:1
This missense variant replaces alanine with valine at codon 766 of the APC 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 APC-related disorders in the literature. This variant has been identified in 4/282134 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. -
APC-related disorder Uncertain:1
The APC c.2297C>T variant is predicted to result in the amino acid substitution p.Ala766Val. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD. In ClinVar, it has been interpreted as uncertain by several laboratories (https://www.ncbi.nlm.nih.gov/clinvar/variation/41522/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at