5-112840942-C-T

Position:

• chr5-112840942-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000038.6(APC):​c.5348C>T​(p.Thr1783Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,382 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 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. T1783S) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 0.311

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 Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.057092935).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APC	NM_000038.6	c.5348C>T	p.Thr1783Ile	missense_variant	16/16	ENST00000257430.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
APC	ENST00000257430.9	c.5348C>T	p.Thr1783Ile	missense_variant	16/16	5	NM_000038.6	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461382 Hom.: 0 Cov.: 54 AF XY: 0.00000138 AC XY: 1 AN XY: 727046

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 25, 2023	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. 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. ClinVar contains an entry for this variant (Variation ID: 236619). This variant has not been reported in the literature in individuals affected with APC-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 1783 of the APC protein (p.Thr1783Ile). -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Nov 17, 2023	- -

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	May 30, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Jan 05, 2021	The p.T1783I variant (also known as c.5348C>T), located in coding exon 15 of the APC gene, results from a C to T substitution at nucleotide position 5348. The threonine at codon 1783 is replaced by isoleucine, an amino acid with similar properties. This amino acid position is poorly 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 this alteration remains unclear. -

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Feb 09, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	13
DANN	Benign	0.94
DEOGEN2	Benign	0.28	T;T
Eigen	Benign	-0.83
Eigen_PC	Benign	-0.64
FATHMM_MKL	Benign	0.26	N
LIST_S2	Benign	0.82	.;T
M_CAP	Benign	0.039	D
MetaRNN	Benign	0.057	T;T
MetaSVM	Benign	-0.83	T
MutationAssessor	Benign	0.0	N;N
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.51	N;N
REVEL	Benign	0.21
Sift	Benign	0.20	T;T
Sift4G	Benign	0.28	T;T
Polyphen		0.0	B;B
Vest4		0.082
MutPred		0.27		Loss of phosphorylation at T1783 (P = 0.0065);Loss of phosphorylation at T1783 (P = 0.0065);
MVP		0.65
ClinPred		0.032	T
GERP RS		2.2
Varity_R		0.022
gMVP		0.33

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: rs878853456; hg19: chr5-112176639;