rs1554088797

Positions:

• chr5-112843560-G-A
• chr5-112843560-G-C
• chr5-112843560-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000038.6(APC):​c.7966G>A​(p.Asp2656Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,718 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: 6.8e-7 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.25

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.85

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.7966G>A	p.Asp2656Asn	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.7966G>A	p.Asp2656Asn	missense_variant	16/16	5	NM_000038.6	ENSP00000257430	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461718 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727166

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: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Oct 24, 2022	The p.D2656N variant (also known as c.7966G>A), located in coding exon 15 of the APC gene, results from a G to A substitution at nucleotide position 7966. The aspartic acid at codon 2656 is replaced by asparagine, an amino acid with highly 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 05, 2023	This missense variant replaces aspartic acid with asparagine at codon 2656 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 not been reported in individuals affected with APC-related disorders in the literature. This variant has not been identified 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	Pathogenic	0.75
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.030
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;D
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.97	.;D
M_CAP	Uncertain	0.091	D
MetaRNN	Pathogenic	0.85	D;D
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Benign	1.0	L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Benign	-2.0	N;N
REVEL	Uncertain	0.46
Sift	Pathogenic	0.0	D;D
Sift4G	Uncertain	0.037	D;D
Polyphen		1.0	D;D
Vest4		0.71
MutPred		0.41		Gain of catalytic residue at D2656 (P = 0.0101);Gain of catalytic residue at D2656 (P = 0.0101);
MVP		0.94
ClinPred		0.95	D
GERP RS		6.2
Varity_R		0.50
gMVP		0.69

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: rs1554088797; hg19: chr5-112179257;