rs1236451833

chr5-112842435-G-A

Variant summary

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

The NM_000038.6(APC):c.6841G>A(p.Glu2281Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,764 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. E2281Q) 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:2
• Conservation: PhyloP100: 4.72

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 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6	c.6841G>A	p.Glu2281Lys	missense_variant	16/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9	c.6841G>A	p.Glu2281Lys	missense_variant	16/16	5	NM_000038.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 250980 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135660

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461764 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727178

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 23, 2017

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. 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: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with APC-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glutamic acid with lysine at codon 2281 of the APC protein (p.Glu2281Lys). The glutamic acid residue is highly conserved and there is a small physicochemical difference between glutamic acid and lysine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 22, 2021

The p.E2281K variant (also known as c.6841G>A), located in coding exon 15 of the APC gene, results from a G to A substitution at nucleotide position 6841. The glutamic acid at codon 2281 is replaced by lysine, 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	Uncertain	0.44
BayesDel_addAF	Uncertain	0.035	T
BayesDel_noAF	Benign	-0.090
Cadd	Uncertain	25
Dann	Uncertain	1.0
DEOGEN2	Benign	0.36	T;T
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Uncertain	0.95	D
M_CAP	Uncertain	0.17	D
MetaRNN	Uncertain	0.50	D;D
MetaSVM	Uncertain	-0.071	T
MutationAssessor	Uncertain	2.1	M;M
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.62	T
PROVEAN	Benign	-1.0	N;N
REVEL	Uncertain	0.36
Sift	Uncertain	0.0050	D;D
Sift4G	Benign	0.61	T;T
Polyphen		0.82	P;P
Vest4		0.50
MutPred		0.43		Gain of methylation at E2281 (P = 0.0184);Gain of methylation at E2281 (P = 0.0184);
MVP		0.74
ClinPred		0.60	D
GERP RS		6.0
Varity_R		0.30
gMVP		0.52

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: rs1236451833; hg19: chr5-112178132;