5-112841460-A-T

Position:

• chr5-112841460-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000038.6(APC):​c.5866A>T​(p.Ile1956Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,534 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 7.14

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]

ENSG00000258864 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.83

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.5866A>T	p.Ile1956Phe	missense_variant	16/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.5866A>T	p.Ile1956Phe	missense_variant	16/16	5	NM_000038.6	ENSP00000257430.4
ENSG00000258864	ENST00000520401.1	n.228+12488A>T		intron_variant		3		ENSP00000454861.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461534 Hom.: 0 Cov.: 65 AF XY: 0.00000138 AC XY: 1 AN XY: 727108

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Jul 21, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	May 22, 2023	This sequence change replaces isoleucine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 1956 of the APC protein (p.Ile1956Phe). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with APC-related conditions. ClinVar contains an entry for this variant (Variation ID: 233259). 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. 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. -

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 10, 2015	The p.I1956F variant (also known as c.5866A>T), located in coding exon 15 of the APC gene, results from an A to T substitution at nucleotide position 5866. The isoleucine at codon 1956 is replaced by phenylalanine, an amino acid with highly similar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6501 samples (13002 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.003% (greater than 32000 alleles tested) in our clinical cohort. This amino acid position is well conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. Since supporting evidence is limited at this time, the clinical significance of p.I1956F remains unclear. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Sep 23, 2021	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.49
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Uncertain	23
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.62	D;D
Eigen	Uncertain	0.47
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	.;D
M_CAP	Benign	0.066	D
MetaRNN	Pathogenic	0.83	D;D
MetaSVM	Benign	-0.30	T
MutationAssessor	Benign	1.0	L;L
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-1.9	N;N
REVEL	Uncertain	0.58
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.014	D;D
Polyphen		0.97	D;D
Vest4		0.80
MutPred		0.50		Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);
MVP		0.94
ClinPred		0.88	D
GERP RS		4.8
Varity_R		0.39
gMVP		0.45

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: rs749597014; hg19: chr5-112177157;