rs1554072636

Positions:

• chr5-112780884-A-G
• chr5-112780884-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_000038.6(APC):​c.626A>G​(p.Asp209Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,046 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: 6.9e-7 (0 hom.)
• Consequence: APC NM_000038.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 8.61

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]

APC (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a coiled_coil_region (size 121) in uniprot entity APC_HUMAN there are 9 pathogenic changes around while only 3 benign (75%) in NM_000038.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.788

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
APC	NM_000038.6	c.626A>G	p.Asp209Gly	missense_variant	6/16	ENST00000257430.9	NP_000029.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
APC	ENST00000257430.9	c.626A>G	p.Asp209Gly	missense_variant	6/16	5	NM_000038.6	ENSP00000257430.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459046 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 725902

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: 9.01e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Jun 03, 2019

Variant summary: APC c.626A>G (p.Asp209Gly) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 249476 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.626A>G in individuals affected with Familial Adenomatous Polyposis and no experimental evidence demonstrating its impact on protein function have been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Familial adenomatous polyposis 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 31, 2023

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. RNA analysis performed to evaluate the impact of this missense change on mRNA splicing indicates it does not significantly alter splicing (Invitae). ClinVar contains an entry for this variant (Variation ID: 929146). 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 aspartic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 209 of the APC protein (p.Asp209Gly). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 05, 2022

The p.D209G variant (also known as c.626A>G), located in coding exon 5 of the APC gene, results from an A to G substitution at nucleotide position 626. The aspartic acid at codon 209 is replaced by glycine, an amino acid with similar properties. 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 this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.78	.;D;D;T
Eigen	Uncertain	0.67
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.87	D;.;D;D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.79	D;D;D;D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Uncertain	2.1	.;M;M;.
PrimateAI	Uncertain	0.73	T
PROVEAN	Uncertain	-4.2	D;D;D;D
REVEL	Pathogenic	0.82
Sift	Uncertain	0.0020	D;D;D;D
Sift4G	Uncertain	0.0060	D;D;D;D
Polyphen		0.98	.;D;D;.
Vest4		0.85, 0.86
MutPred		0.31		.;Gain of loop (P = 0.0166);Gain of loop (P = 0.0166);Gain of loop (P = 0.0166);
MVP		0.99
ClinPred		0.99	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.62
gMVP		0.46

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1554072636; hg19: chr5-112116581;