5-112819037-A-G

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 0P and 10B. BP4_Strong BP6 BP7 BS2

The NM_000038.6(APC):c.1005A>G(p.Leu335=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000489 in 1,614,098 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L335L) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000085 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000045 (0 hom.)
• Consequence: APC NM_000038.6 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:11
• Conservation: PhyloP100: 1.30

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 Benign. Variant got -10 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.54).
• BP6: Variant 5-112819037-A-G is Benign according to our data. Variant chr5-112819037-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 92339.We mark this variant Likely_benign, oryginal submissions are: {Benign=9, Uncertain_significance=1, Likely_benign=1}. Variant chr5-112819037-A-G is described in Lovd as [Benign].
• BP7: Synonymous conserved (PhyloP=1.3 with no splicing effect.
• BS2: High AC in GnomAd at 13 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6	c.1005A>G	p.Leu335=	synonymous_variant	10/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9	c.1005A>G	p.Leu335=	synonymous_variant	10/16	5	NM_000038.6	P1

Frequencies

GnomAD3 genomes AF: 0.0000854 AC: 13 AN: 152150 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: 0.00250

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: 0.000159 AC: 40 AN: 251080 Hom.: 1 AF XY: 0.000162 AC XY: 22 AN XY: 135690

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00201

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000924

Gnomad NFE exome AF: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000451 AC: 66 AN: 1461830 Hom.: 0 Cov.: 33 AF XY: 0.0000523 AC XY: 38 AN XY: 727218

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00131

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.000132

GnomAD4 genome AF: 0.0000854 AC: 13 AN: 152268 Hom.: 0 Cov.: 32 AF XY: 0.0000806 AC XY: 6 AN XY: 74460

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00250

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000756

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:11

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not specified Benign:4

Benign, criteria provided, single submitter	clinical testing	GeneDx	Jul 21, 2015	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Dec 11, 2017	Variant summary: The APC c.1005A>G (p.Leu335Leu) 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. 4/5 splice prediction tools predict no significant impact on normal splicing. ESE finder predicts the creation of SRp40 binding site. However, these predictions have yet to be confirmed by functional studies. This variant was found in 41/276982 control chromosomes, predominantly observed in the East Asian subpopulation at a frequency of 0.001962 (37/18854). This frequency is about 27 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. This variant was reported in one breast patient but also in controls (Chang_2016) and also as a somatic occurrence (Chang_2016). In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as likely benign/benign. Taken together, this variant is classified as benign. -
Benign, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Aug 15, 2023	- -
Benign, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Dec 27, 2019	- -

Hereditary cancer-predisposing syndrome Benign:3

Benign, criteria provided, single submitter	curation	Sema4, Sema4	Feb 10, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 17, 2016	- -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Nov 24, 2015	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. -

Familial adenomatous polyposis 1 Benign:2

Benign, criteria provided, single submitter	clinical testing	Invitae	Jan 29, 2024	- -
Benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Feb 29, 2024	This variant is considered benign. This variant is a silent/synonymous amino acid change and it is not expected to impact splicing. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Apr 19, 2013

- -

Carcinoma of colon Benign:1

Likely benign, no assertion criteria provided

clinical testing

Department of Pathology and Laboratory Medicine, Sinai Health System

-

The APC p.Leu335Leu variant was identified in 3 of 384 proband chromosomes (frequency: 0.0078125) from Taiwense individuals or families with CRC or breast cancer (Chang YC 2016, Chang YS 2016). There was found to be no observed association between breast cancer risk and the variant (Chang YS 2016). The variant was also identified in dbSNP (ID: rs3797704) “With Likely benign,other allele”, ClinVar (with conflicting interpretations of pathogenicity; submitters: benign by Invitae and GeneDx, likely benign by Ambry Genetics and Department of Pathology and Laboratory Medicine (Sinai Health System), and uncertain significance by EGL Genetic Diagnostics (Eurofins Clinical Diagnostics)), Clinvitae (4x), Cosmic (2x in carcinomas of the large intestine), and Zhejiang Colon Cancer Database (1x), but was not identified in Genesight-COGR. The variant was identified in control databases in 40 of 276782 chromosomes at a frequency of 0.0001 increasing the likelihood that this may be a low frequency benign variant in certain populations of origin (Genome Aggregation Consortium Feb 27, 2017), being identified in the following populations: European Non-Finnish in 1 of 126350 chromosomes (frequency: 0.000008), East Asian in 37 of 1854 chromosomes (frequency: 0.002), and European Finnish in 2 of 25792 chromosomes (frequency: 0.00008). The p.Leu335= 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 summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -

Classic or attenuated familial adenomatous polyposis Benign:1

Benign, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jan 11, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.54
Cadd	Benign	8.5
Dann	Benign	0.78

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs3797704; hg19: chr5-112154734; COSMIC: COSV57331781; COSMIC: COSV57331781;