rs863224537
Variant summary
Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4BS2
The NM_000038.6(APC):c.1440A>C(p.Gln480His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,613,628 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).
Frequency
Consequence
NM_000038.6 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -5 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152146Hom.: 0 Cov.: 32
GnomAD4 exome AF: 0.00000547 AC: 8AN: 1461482Hom.: 0 Cov.: 30 AF XY: 0.00000550 AC XY: 4AN XY: 727046
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152146Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74326
ClinVar
Submissions by phenotype
Familial adenomatous polyposis 1 Uncertain:2
This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 480 of the APC protein (p.Gln480His). This variant is present in population databases (no rsID available, gnomAD no frequency). 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: 245917). 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. -
The APC p.Gln480His variant was not identified in the literature nor was it identified in the dbSNP, NHLBI Exome Sequencing Project (Exome Variant Server), Exome Aggregation Consortium (ExAC) database, HGMD, COSMIC, MutDB, “Mismatch Repair Genes Variant Database”, “MMR Gene Unclassified Variants Database”, InSiGHT Colon Cancer Gene Variant Database, “Zhejiang Colon Cancer Database”, the ClinVar database, GeneInsight VariantWire database. The variant was only identified in UMD (1X as a UV variant). The p.Gln480 residue is not 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 2 of 5 in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) predict a greater than 10% difference in splicing; this is not very predictive of pathogenicity. 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 unknown significance. -
not provided Uncertain:2
Not observed at significant frequency in large population cohorts (Lek 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 18199528) -
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not specified Uncertain:1
Variant summary: APC c.1440A>C (p.Gln480His) results in a non-conservative amino acid change located in the Armadillo domain of the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant was absent in 251156 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1440A>C in individuals affected with Familial Adenomatous Polyposis and no experimental evidence demonstrating its impact on protein function have been reported. Three ClinVar submissions (evaluation after 2014) cite the variant twice as uncertain significance and once as pathogenic. 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 glutamine with histidine at codon 480 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 1/245924 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. -
Hereditary cancer-predisposing syndrome Uncertain:1
The p.Q480H variant (also known as c.1440A>C), located in coding exon 11 of the APC gene, results from an A to C substitution at nucleotide position 1440. The glutamine at codon 480 is replaced by histidine, an amino acid with highly similar properties. Missense alterations in APC are not a common cause of disease (Spier I et al. Genet Med. 2024 Feb;26(2):100992). This amino acid position is highly conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. Based on the available evidence, the clinical significance of this variant remains unclear. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at