dbSNP rs878853432: APC:p.Ser932* (chr5-112838389-C-A) – ACMG Classification: Pathogenic (18 pts)

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000038.6(APC):c.2795C>A(p.Ser932*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000657 in 152,214 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Consequence

APC
NM_000038.6 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 4.49

Variant links:

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 links:

ENSG00000258864 (HGNC:):

ENSG00000258864 links:

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 237 pathogenic variants in the truncated region.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 5-112838389-C-A is Pathogenic according to our data. Variant chr5-112838389-C-A is described in ClinVar as [Pathogenic]. Clinvar id is 411362.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr5-112838389-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
APC	NM_000038.6 link	c.2795C>A	p.Ser932*	stop_gained	Exon 16 of 16	ENST00000257430.9	NP_000029.2	P25054-1Q4LE70

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9 link	c.2795C>A	p.Ser932*	stop_gained	Exon 16 of 16	5	NM_000038.6	ENSP00000257430.4		P25054-1
ENSG00000258864	ENST00000520401.1 link	n.228+9417C>A		intron_variant	Intron 3 of 7	3		ENSP00000454861.1		H3BNH8

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152214

Hom.:

Cov.:

show subpopulations

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

GnomAD4 exome

Cov.:

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152214

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74358

show subpopulations

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

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Familial adenomatous polyposis 1

Pathogenic:2

May 05, 2023

Myriad Genetics, Inc.

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered pathogenic. This variant creates a termination codon and is predicted to result in premature protein truncation. -

Apr 26, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. A different truncation (p.Tyr2645Lysfs*14) that lies downstream of this variant has been determined to be pathogenic (PMID: 9824584, 1316610, 27081525, 8381579, 22135120, Invitae). This suggests that deletion of this region of the APC protein is causative of disease. This variant is expected to disrupt the EB1 and HDLG binding sites, which mediate interactions with the cytoskeleton (PMID: 15311282, 17293347). While functional studies have not been performed to directly test the effect on APC protein function, this suggests that disruption of the C-terminal portion of the protein is functionally important. ClinVar contains an entry for this variant (Variation ID: 411362). This premature translational stop signal has been observed in individual(s) with familial adenomatous polyposis (PMID: 1316610, 1338764, 10083733, 20685668). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Ser932*) in the APC gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 1912 amino acid(s) of the APC protein. -

not provided

Pathogenic:1

Jun 27, 2017

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome

Pathogenic:1

Mar 09, 2023

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S932* pathogenic mutation (also known as c.2795C>A), located in coding exon 15 of the APC gene, results from a C to A substitution at nucleotide position 2795. This changes the amino acid from a serine to a stop codon within coding exon 15. This alteration occurs at the 3' terminus of theAPC gene, is not expected to trigger nonsense-mediated mRNA decay, and only impacts the last 1911 amino acids of the protein. However, premature stop codons are typically deleterious in nature and the impacted region is critical for protein function and a significant portion of the protein is affected (Ambry internal data). This mutation has been previously identified in a patient with a clinical diagnosis of Familial Adenomatous Polyposis (FAP) (Miyoshi Y et al. Proc. Natl. Acad. Sci. U.S.A. 1992 May;89:4452-6; Lagarde A et al. J. Med. Genet. 2010 Oct;47:721-2). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.56

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.78

Eigen_PC

Uncertain

0.64

FATHMM_MKL

Pathogenic

0.98

Vest4

0.92, 0.91

GERP RS

5.8

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over