rs730882128

Positions:

• chr5-112840500-G-A
• chr5-112840500-G-C
• chr5-112840500-G-T

Variant summary

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

The NM_000038.6(APC):​c.4906G>A​(p.Asp1636Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.28

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 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.4906G>A	p.Asp1636Asn	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.4906G>A	p.Asp1636Asn	missense_variant	16/16	5	NM_000038.6	ENSP00000257430.4
ENSG00000258864	ENST00000520401.1	n.228+11528G>A		intron_variant		3		ENSP00000454861.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251212 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135762

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 66

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 11, 2024

The p.D1636N variant (also known as c.4906G>A), located in coding exon 15 of the APC gene, results from a G to A substitution at nucleotide position 4906. The aspartic acid at codon 1636 is replaced by asparagine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. Missense alterations in APC are not a common cause of disease (Spier I et al. Genet Med. 2024 Feb;26(2):100992). Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	0.011	T
BayesDel_noAF	Benign	-0.22
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D;D
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.49
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.96	.;D
M_CAP	Benign	0.051	D
MetaRNN	Uncertain	0.51	D;D
MetaSVM	Uncertain	0.22	D
MutationAssessor	Uncertain	2.1	M;M
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	-1.7	N;N
REVEL	Uncertain	0.44
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.0090	D;D
Polyphen		0.33	B;B
Vest4		0.50
MutPred		0.40		Gain of catalytic residue at D1636 (P = 0.0355);Gain of catalytic residue at D1636 (P = 0.0355);
MVP		0.87
ClinPred		0.73	D
GERP RS		5.6
Varity_R		0.21
gMVP		0.40

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: rs730882128; hg19: chr5-112176197;