5-112838317-C-G

Position:

• chr5-112838317-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 4P and 1B. PM1 PM2 BP4

The NM_000038.6(APC):​c.2723C>G​(p.Ser908Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,614,108 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:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 3.70

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]

ENSG00000258864 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM1: In a modified_residue Phosphoserine (size 0) in uniprot entity APC_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3024013).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.2723C>G	p.Ser908Cys	missense_variant	16/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.2723C>G	p.Ser908Cys	missense_variant	16/16	5	NM_000038.6	ENSP00000257430.4
ENSG00000258864	ENST00000520401.1	n.228+9345C>G		intron_variant		3		ENSP00000454861.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152240 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251040 Hom.: 0 AF XY: 0.00 AC XY: 0 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: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461868 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727236

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152240 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74372

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 16, 2022	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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C15"). ClinVar contains an entry for this variant (Variation ID: 374938). This variant has not been reported in the literature in individuals affected with APC-related conditions. This variant is present in population databases (rs746393911, gnomAD 0.0009%). This sequence change replaces serine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 908 of the APC protein (p.Ser908Cys). -
Uncertain significance, no assertion criteria provided	clinical testing	Knight Diagnostic Laboratories, Oregon Health and Sciences University	Sep 26, 2015	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 05, 2024	- -

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Sep 20, 2024	The p.S908C variant (also known as c.2723C>G), located in coding exon 15 of the APC gene, results from a C to G substitution at nucleotide position 2723. The serine at codon 908 is replaced by cysteine, an amino acid with dissimilar 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. Missense alterations in APC are not a common cause of disease (Spier I et al. Genet Med. 2024 Feb;26(2):100992). Based on the available evidence, the clinical significance of this variant remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Jul 03, 2019	This missense variant replaces serine with cysteine at codon 908 of the APC protein. Computational prediction tools and conservation analyses are inconclusive regarding the impact of this variant on the protein function. Computational splicing tools suggest that this variant may not impact RNA splicing. To our knowledge, functional assays have not been performed for this variant nor has this variant been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 1/251040 chromosomes in the general population by the Genome Aggregation Database (gnomAD). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.030
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.71	.;D;D;D
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.85	T;.;T;T
M_CAP	Uncertain	0.22	D
MetaRNN	Benign	0.30	T;T;T;T
MetaSVM	Uncertain	0.78	D
MutationAssessor	Benign	1.6	.;L;L;.
PrimateAI	Benign	0.42	T
PROVEAN	Benign	-0.67	N;N;N;N
REVEL	Uncertain	0.41
Sift	Benign	0.034	D;D;D;D
Sift4G	Benign	0.065	T;T;T;T
Polyphen		0.94	.;P;P;.
Vest4		0.29, 0.23
MutPred		0.21		.;Loss of glycosylation at S908 (P = 0.0215);Loss of glycosylation at S908 (P = 0.0215);Loss of glycosylation at S908 (P = 0.0215);
MVP		0.81
ClinPred		0.34	T
GERP RS		5.0
Varity_R		0.16
gMVP		0.43

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: rs746393911; hg19: chr5-112174014;