rs777456713

Positions:

• chr5-112767228-T-C
• chr5-112767228-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000038.6(APC):​c.260T>C​(p.Leu87Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 4.70

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 Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.260T>C	p.Leu87Pro	missense_variant	4/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.260T>C	p.Leu87Pro	missense_variant	4/16	5	NM_000038.6	ENSP00000257430	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

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	Sep 21, 2022	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. 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 leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 87 of the APC protein (p.Leu87Pro). -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Feb 28, 2024	- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2023

The p.L87P variant (also known as c.260T>C), located in coding exon 3 of the APC gene, results from a T to C substitution at nucleotide position 260. The leucine at codon 87 is replaced by proline, an amino acid with similar properties. This amino acid position is conserved. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.38	T;.;D;D;T
Eigen	Uncertain	0.41
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.85	D;D;.;D;D
M_CAP	Uncertain	0.099	D
MetaRNN	Uncertain	0.54	D;D;D;D;D
MetaSVM	Uncertain	0.18	D
MutationAssessor	Benign	0.55	.;.;N;N;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.0	D;N;N;N;N
REVEL	Uncertain	0.61
Sift	Uncertain	0.021	D;D;D;D;D
Sift4G	Benign	0.070	T;D;T;T;T
Polyphen		0.90	.;.;P;P;.
Vest4		0.87, 0.96
MutPred		0.28		Gain of loop (P = 0.0097);.;Gain of loop (P = 0.0097);Gain of loop (P = 0.0097);Gain of loop (P = 0.0097);
MVP		0.98
ClinPred		0.89	D
GERP RS		5.5
Varity_R		0.35
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: rs777456713; hg19: chr5-112102925;