rs774964663

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM1PM2BP4_Moderate

The NM_000038.6(APC):c.442C>A(p.Leu148Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000025 in 1,601,534 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L148F) has been classified as Uncertain significance.

Frequency

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

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

APC
NM_000038.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 4.44

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:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM1

In a helix (size 37) in uniprot entity APC_HUMAN there are 6 pathogenic changes around while only 2 benign (75%) in NM_000038.6

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.13283283).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6 linkuse as main transcript	c.442C>A	p.Leu148Ile	missense_variant	5/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9 linkuse as main transcript	c.442C>A	p.Leu148Ile	missense_variant	5/16	5	NM_000038.6	P1	P25054-1

Frequencies

GnomAD3 genomes

AF:

0.00000662

AC:

AN:

151162

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

GnomAD3 exomes

AF:

0.00000812

AC:

AN:

246440

Hom.:

AF XY:

0.00000752

AC XY:

AN XY:

132928

show subpopulations

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:

0.0000179

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000207

AC:

AN:

1450372

Hom.:

Cov.:

AF XY:

0.00000416

AC XY:

AN XY:

721366

show subpopulations

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:

0.00000271

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000662

AC:

AN:

151162

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

73704

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

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jun 06, 2024	The p.L148I variant (also known as c.442C>A), located in coding exon 4 of the APC gene, results from a C to A substitution at nucleotide position 442. The leucine at codon 148 is replaced by isoleucine, an amino acid with highly similar properties. This alteration was detected in a cohort of 1058 unselected colorectal cancer patients undergoing a 25-gene panel test (Yurgelun MB et al. J Clin Oncol. 2017 Apr;35:1086-1095). Missense alterations in APC are not a common cause of disease (Spier I et al. Genet Med. 2024 Feb;26(2):100992). This amino acid position is highly conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. 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	Jan 03, 2023	This missense variant replaces leucine with isoleucine at codon 148 of the APC protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with melanoma and colorectal cancer in the literature (PMID: 28135145, 29684080). This variant has been identified in 2/246440 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The 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. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Oct 31, 2021	- -

Familial adenomatous polyposis 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 17, 2024

This sequence change replaces leucine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 148 of the APC protein (p.Leu148Ile). This variant is present in population databases (rs774964663, gnomAD 0.002%). This missense change has been observed in individual(s) with colorectal cancer (PMID: 28135145). ClinVar contains an entry for this variant (Variation ID: 485091). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt APC protein function with a negative predictive value of 95%. 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. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

May 01, 2024

APC: PM2, BP1 -

Classic or attenuated familial adenomatous polyposis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Oct 02, 2023

This missense variant replaces leucine with isoleucine at codon 148 of the APC protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with melanoma and colorectal cancer in the literature (PMID: 28135145, 29684080). This variant has been identified in 2/246440 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The 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

0.099

BayesDel_addAF

Uncertain

0.055

BayesDel_noAF

Benign

-0.14

CADD

Benign

DANN

Benign

0.87

Eigen

Benign

-0.16

Eigen_PC

Benign

0.079

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.84

T;.;T;T

M_CAP

Benign

0.028

MetaRNN

Benign

0.13

T;T;T;T

MetaSVM

Benign

-0.36

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Pathogenic

0.80

PROVEAN

Benign

0.61

N;N;N;N

REVEL

Uncertain

0.32

Sift

Benign

0.59

T;T;T;T

Sift4G

Benign

0.94

T;T;T;T

Polyphen

0.094

.;B;B;.

Vest4

0.47, 0.46

MutPred

0.30

.;Loss of helix (P = 0.0033);Loss of helix (P = 0.0033);Loss of helix (P = 0.0033);

MVP

0.76

ClinPred

0.44

GERP RS

5.3

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.24

gMVP

0.25

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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