chr5-112815526-C-T

Position:

• chr5-112815526-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000038.6(APC):​c.866C>T​(p.Ala289Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 4.74

Genes affected

APC (HGNC:583): (APC regulator of WNT signaling pathway) This gene encodes a tumor suppressor protein that acts as an antagonist of the Wnt signaling pathway. It is also involved in other processes including cell migration and adhesion, transcriptional activation, and apoptosis. Defects in this gene cause familial adenomatous polyposis (FAP), an autosomal dominant pre-malignant disease that usually progresses to malignancy. Mutations in the APC gene have been found to occur in most colorectal cancers, where disease-associated mutations tend to be clustered in a small region designated the mutation cluster region (MCR) and result in a truncated protein product. [provided by RefSeq, Jun 2022]

APC (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.32602274).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.866C>T	p.Ala289Val	missense_variant	9/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.866C>T	p.Ala289Val	missense_variant	9/16	5	NM_000038.6	ENSP00000257430.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	May 25, 2020	In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. This sequence change replaces alanine with valine at codon 289 of the APC protein (p.Ala289Val). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and valine. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a APC-related disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 12, 2024	- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 17, 2021

The p.A289V variant (also known as c.866C>T), located in coding exon 8 of the APC gene, results from a C to T substitution at nucleotide position 866. The alanine at codon 289 is replaced by valine, an amino acid with similar properties. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.62	.;D;D;T
Eigen	Uncertain	0.20
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.94	D;.;D;D
M_CAP	Benign	0.075	D
MetaRNN	Benign	0.33	T;T;T;T
MetaSVM	Uncertain	0.57	D
MutationAssessor	Uncertain	2.3	.;M;M;.
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-1.4	N;N;N;N
REVEL	Uncertain	0.39
Sift	Benign	0.046	D;T;T;D
Sift4G	Benign	0.12	T;T;T;T
Polyphen		0.22	.;B;B;.
Vest4		0.60, 0.71
MutPred		0.10		.;Loss of helix (P = 0.0123);Loss of helix (P = 0.0123);Loss of helix (P = 0.0123);
MVP		0.84
ClinPred		0.92	D
GERP RS		5.1
Varity_R		0.19
gMVP		0.61

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1554079159; hg19: chr5-112151223; COSMIC: COSV57335635;