chr5-112840581-G-A

Position:

• chr5-112840581-G-A

Variant summary

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

The NM_000038.6(APC):​c.4987G>A​(p.Glu1663Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,838 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1663D) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 6.44

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]

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=0.34125397).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6	c.4987G>A	p.Glu1663Lys	missense_variant	16/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9	c.4987G>A	p.Glu1663Lys	missense_variant	16/16	5	NM_000038.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461838 Hom.: 0 Cov.: 66 AF XY: 0.00 AC XY: 0 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

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	Dec 06, 2023	This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 1663 of the APC protein (p.Glu1663Lys). 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: 216168). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Nov 26, 2023	- -

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 18, 2023	The p.E1663K variant (also known as c.4987G>A), located in coding exon 15 of the APC gene, results from a G to A substitution at nucleotide position 4987. The glutamic acid at codon 1663 is replaced by lysine, an amino acid with similar properties. This amino acid position is not 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Sep 07, 2021	This missense variant replaces glutamic acid with lysine at codon 1663 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 hereditary cancer in the literature. This variant has not been identified 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. -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Mendelics

May 04, 2022

- -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Nov 10, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.52	D;D
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.99	.;D
M_CAP	Benign	0.061	D
MetaRNN	Benign	0.34	T;T
MetaSVM	Uncertain	-0.11	T
MutationAssessor	Benign	1.6	L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-1.2	N;N
REVEL	Uncertain	0.35
Sift	Uncertain	0.026	D;D
Sift4G	Uncertain	0.051	T;T
Polyphen		0.83	P;P
Vest4		0.41
MutPred		0.30		Gain of ubiquitination at E1663 (P = 0.006);Gain of ubiquitination at E1663 (P = 0.006);
MVP		0.95
ClinPred		0.72	D
GERP RS		6.2
Varity_R		0.35
gMVP		0.37

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: rs758987855; hg19: chr5-112176278; COSMIC: COSV99072973; COSMIC: COSV99072973;