rs1060503282

chr5-112837691-G-Achr5-112837691-G-Cchr5-112837691-G-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000038.6(APC):c.2097G>A(p.Trp699Ter) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,870 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: APC NM_000038.6 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 9.60

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 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 997 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-112837691-G-A is Pathogenic according to our data. Variant chr5-112837691-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 411387.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr5-112837691-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6	c.2097G>A	p.Trp699Ter	stop_gained	16/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9	c.2097G>A	p.Trp699Ter	stop_gained	16/16	5	NM_000038.6	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461870 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727232

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 16, 2023	This sequence change creates a premature translational stop signal (p.Trp699*) in the APC gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 2145 amino acid(s) of the APC protein. This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with familial adenomatous polyposis (PMID: 8544194, 10083733). ClinVar contains an entry for this variant (Variation ID: 411387). 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. 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. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	May 04, 2023	This variant is considered pathogenic. This variant creates a termination codon and is predicted to result in premature protein truncation. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

May 20, 2021

This variant is expected to result in the loss of a functional protein. Found in at least one patient with expected phenotype for this gene. This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 30, 2021

The p.W699* pathogenic mutation (also known as c.2097G>A), located in coding exon 15 of the APC gene, results from a G to A substitution at nucleotide position 2097. This changes the amino acid from a tryptophan to a stop codon within coding exon 15. This alteration has been identified in multiple familial adenomatous polyposis families (Bunyan DJ et al. J. Med. Genet., 1995 Sep;32:728-31; Li J et al. Gut, 2020 07;69:1283-1293). 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	D
BayesDel_noAF	Pathogenic	0.66
Cadd	Pathogenic	38
Dann	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D
Vest4		0.99, 0.98
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs1060503282; hg19: chr5-112173388; COSMIC: COSV57342069;