5-112827187-A-T

Position:

• chr5-112827187-A-T

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_000038.6(APC):​c.1488A>T​(p.Thr496Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000111 in 1,613,964 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00023 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000099 (1 hom.)
• Consequence: APC NM_000038.6 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:15
• Conservation: PhyloP100: -0.480

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 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).
• BP6: Variant 5-112827187-A-T is Benign according to our data. Variant chr5-112827187-A-T is described in ClinVar as [Likely_benign]. Clinvar id is 135684.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr5-112827187-A-T is described in Lovd as [Likely_benign]. Variant chr5-112827187-A-T is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=-0.48 with no splicing effect.
• BS1: Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.00023 (35/152340) while in subpopulation EAS AF= 0.00674 (35/5196). AF 95% confidence interval is 0.00498. There are 0 homozygotes in gnomad4. There are 23 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 35 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.1488A>T	p.Thr496Thr	synonymous_variant	12/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.1488A>T	p.Thr496Thr	synonymous_variant	12/16	5	NM_000038.6	ENSP00000257430.4
ENSG00000258864	ENST00000520401.1	n.-28A>T		upstream_gene_variant		3		ENSP00000454861.1

Frequencies

GnomAD3 genomes AF: 0.000230 AC: 35 AN: 152222 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00672

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000474 AC: 119 AN: 251268 Hom.: 1 AF XY: 0.000493 AC XY: 67 AN XY: 135784

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00642

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000985 AC: 144 AN: 1461624 Hom.: 1 Cov.: 33 AF XY: 0.000100 AC XY: 73 AN XY: 727118

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00343

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000994

GnomAD4 genome AF: 0.000230 AC: 35 AN: 152340 Hom.: 0 Cov.: 33 AF XY: 0.000309 AC XY: 23 AN XY: 74494

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00674

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000434 Hom.: 0

Bravo AF: 0.000317

Asia WGS AF: 0.00115 AC: 4 AN: 3478

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:15

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:5

Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 03, 2015	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jun 09, 2017	Variant summary: The APC c.1488A>T (p.Thr496Thr) variant involves the alteration of a non-conserved nucleotide, resulting in a synonymous change. One in silico tool predicts a damaging outcome for this variant. 5/5 splice prediction tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. This variant was found in 55/121488 control chromosomes, predominantly observed in the East Asian subpopulation at a frequency of 0.006028 (52/8626). This frequency is about 84 times the estimated maximal expected allele frequency of a pathogenic APC variant (0.0000714), suggesting this is likely a benign polymorphism found primarily in the populations of East Asian origin. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as likely benign/benign. Taken together, this variant is classified as benign. -
Likely benign, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Benign, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Mar 20, 2023	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

Hereditary cancer-predisposing syndrome Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Jul 24, 2014	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -
Benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 30, 2016	- -
Benign, criteria provided, single submitter	curation	Sema4, Sema4	Mar 19, 2021	- -

not specified Benign:2

Benign, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Likely benign, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Aug 15, 2023	- -

Familial adenomatous polyposis 1 Benign:2

Benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Mar 04, 2024	This variant is considered benign. This variant is a silent/synonymous amino acid change and it is not expected to impact splicing. -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 28, 2024	- -

Carcinoma of colon Benign:1

Benign, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The APC p.Thr496= variant was identified in 1 of 338 proband chromosomes (frequency: 0.01) from individuals or families with colorectal cancer, and was not identified in 244 control chromosomes from healthy individuals (Chang 2016, Chen 2006). The variant was also identified in dbSNP (ID: rs9282599) as “With Likely benign allele”, ClinVar (classified as benign by Invitae, Color Genomics and Integrated Genetics/Laboratory Corporation of America; as likely benign by Ambry Genetics and Quest Diagnostics Nichols Institute San Juan Capistrano), Clinvitae, LOVD 3.0 (Probably does not affect function), or Zhejiang Colon Cancer Database (2X). The variant was not identified in GeneInsight-COGR, Cosmic, or UMD-LSDB databases. The variant was identified in control databases in 123 of 277014 chromosomes (1 homozygous) at a frequency of 0.0004 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). Breakdown of the observations by population include East Asian in 122 of 18852 chromosomes (freq: 0.01), Finnish in 1 of 25786 chromosomes (freq: 0.00004), while the variant was not observed in the African, Other, Latino, European, Ashkenazi Jewish, and South Asian populations. The p.Thr496= variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. In addition, in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer, HumanSpliceFinder) do not predict a difference in splicing. In summary, based on the above information this variant meets our laboratory's criteria to be classified as benign. -

APC-Associated Polyposis Disorders Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

APC-related disorder Benign:1

Benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 11, 2019

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	7.4
DANN	Benign	0.74

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: rs9282599; hg19: chr5-112162884;