5-112842264-A-G
Variant summary
Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_000038.6(APC):āc.6670A>Gā(p.Ile2224Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000124 in 1,613,940 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 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. I2224M) 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
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ACMG classification
Our verdict: Likely_benign. The variant received -2 ACMG points.
Transcripts
RefSeq
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt | 
|---|---|---|---|---|---|---|---|---|---|---|
| APC | ENST00000257430.9 | c.6670A>G | p.Ile2224Val | missense_variant | Exon 16 of 16 | 5 | NM_000038.6 | ENSP00000257430.4 | ||
| ENSG00000258864 | ENST00000520401.1 | n.228+13292A>G | intron_variant | Intron 3 of 7 | 3 | ENSP00000454861.1 | 
Frequencies
GnomAD3 genomes  0.0000197  AC: 3AN: 152178Hom.:  0  Cov.: 32 show subpopulations 
GnomAD2 exomes  AF:  0.00000800  AC: 2AN: 249988 AF XY:  0.00   show subpopulations 
GnomAD4 exome  AF:  0.0000116  AC: 17AN: 1461762Hom.:  0  Cov.: 34 AF XY:  0.0000110  AC XY: 8AN XY: 727192 show subpopulations 
Age Distribution
GnomAD4 genome  0.0000197  AC: 3AN: 152178Hom.:  0  Cov.: 32 AF XY:  0.0000134  AC XY: 1AN XY: 74370 show subpopulations  ā ļø The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. 
Age Distribution
ClinVar
Submissions by phenotype
Familial adenomatous polyposis 1    Uncertain:2 
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This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 2224 of the APC protein (p.Ile2224Val). This variant is present in population databases (rs374597207, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with APC-related conditions. ClinVar contains an entry for this variant (Variation ID: 181814). 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 APC protein function with a negative predictive value of 95%. 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 provided    Uncertain:1Benign:1 
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; Identified in at least one individual undergoing hereditary cancer multigene panel testing in the literature (Yorczyk 2015); This variant is associated with the following publications: (PMID: 18199528, 25318351) -
APC: BP1, BP4, BS2 -
Hereditary cancer-predisposing syndrome    Uncertain:1Benign:1 
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The p.I2224V variant (also known as c.6670A>G), located in coding exon 15 of the APC gene, results from an A to G substitution at nucleotide position 6670. The isoleucine at codon 2224 is replaced by valine, an amino acid with highly similar properties. This alteration has been reported in a cohort of 105 patients who were tested with a hereditary cancer multi-gene panel test, but no specific clinical data was provided for the carrier(s) of this variant (Yorczyk A et al. Clin. Genet., 2015 Sep;88:278-82). This amino acid position is well 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.6670A>G (p.Ile2224Val) results in a conservative amino acid change located in the Adenomatous polyposis coli protein basic domain (IPR009234) of 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 249988 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.6670A>G has been reported in the literature as a VUS in settings of multigene panel testing in the cancer genetics clinic (example, Yorczyk_2015). These report(s) do 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. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -
Gastric cancer;C0346629:Colorectal cancer;C1851124:Desmoid disease, hereditary;C2239176:Hepatocellular carcinoma;C2713442:Familial adenomatous polyposis 1;C4749917:Gastric adenocarcinoma and proximal polyposis of the stomach    Uncertain:1 
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Classic or attenuated familial adenomatous polyposis    Uncertain:1 
This missense variant replaces isoleucine with valine at codon 2224 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). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with hereditary cancer but has been reported in healthy control individuals (PMID: 32980694) and an individual undergoing hereditary cancer testing (PMID: 25318351). This variant has been identified in 2/249988 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. -
Computational scores
Source: 
Splicing
 Find out detailed SpliceAI scores and Pangolin per-transcript scores at