chr5-112819330-A-T

Position:

• chr5-112819330-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000038.6(APC):​c.1298A>T​(p.Gln433Leu) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. Q433Q) has been classified as Benign.

• 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: 5.67

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.1298A>T	p.Gln433Leu	missense_variant	10/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.1298A>T	p.Gln433Leu	missense_variant	10/16	5	NM_000038.6	ENSP00000257430.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

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:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 16, 2022

This sequence change replaces glutamine, which is neutral and polar, with leucine, which is neutral and non-polar, at codon 433 of the APC protein (p.Gln433Leu). This variant is not present in population databases (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: 418775). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Mar 30, 2015

This variant is denoted APC c.1298A>T at the cDNA level, p.Gln433Leu (Q433L) at the protein level, and results in the change of a Glutamine to a Leucine (CAG>CTG). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. APC Gln433Leu 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 Glutamine and Leucine differ in polarity, charge, size or other properties, this is considered a non-conservative amino acid substitution. APC Gln433Leu occurs at a position that is conserved across species and is not located in a known functional domain (Azzopardi 2008). In silico analyses are inconsistent regarding the effect this variant may have on protein structure and function. Based on currently available information, it is unclear whether APC Gln433Leu is pathogenic or benign. We consider it to be a variant of uncertain significance. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 25, 2022

The p.Q433L variant (also known as c.1298A>T), located in coding exon 9 of the APC gene, results from an A to T substitution at nucleotide position 1298. The glutamine at codon 433 is replaced by leucine, an amino acid with dissimilar 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.14
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.55	.;D;D;T
Eigen	Uncertain	0.21
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;.;D;D
M_CAP	Uncertain	0.095	D
MetaRNN	Uncertain	0.49	T;T;T;T
MetaSVM	Uncertain	0.37	D
MutationAssessor	Benign	1.4	.;L;L;.
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-3.7	D;D;D;D
REVEL	Uncertain	0.48
Sift	Benign	0.15	T;T;T;T
Sift4G	Benign	0.29	T;T;T;T
Polyphen		0.68	.;P;P;.
Vest4		0.58, 0.60
MutPred		0.31		.;Loss of disorder (P = 0.0582);Loss of disorder (P = 0.0582);Loss of disorder (P = 0.0582);
MVP		0.95
ClinPred		0.77	D
GERP RS		5.8
Varity_R		0.67
gMVP		0.42

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs1064793424; hg19: chr5-112155027;