NM_000038.6:c.71G>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000038.6(APC):​c.71G>A​(p.Arg24Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,442 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R24L) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

APC
NM_000038.6 missense

Scores

6
10
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 9.45

Publications

2 publications found
Variant links:
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 Gene-Disease associations (from GenCC):
  • classic or attenuated familial adenomatous polyposis
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • desmoid tumor
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp
  • familial adenomatous polyposis 1
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
  • gastric adenocarcinoma and proximal polyposis of the stomach
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
  • sarcoma
    Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
  • APC-related attenuated familial adenomatous polyposis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Turcot syndrome with polyposis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Cenani-Lenz syndactyly syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
APCNM_000038.6 linkc.71G>A p.Arg24Gln missense_variant Exon 2 of 16 ENST00000257430.9 NP_000029.2 P25054-1Q4LE70

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
APCENST00000257430.9 linkc.71G>A p.Arg24Gln missense_variant Exon 2 of 16 5 NM_000038.6 ENSP00000257430.4 P25054-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251240
AF XY:
0.00000737
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461442
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
727046
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33466
American (AMR)
AF:
0.0000224
AC:
1
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39642
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86238
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111706
Other (OTH)
AF:
0.00
AC:
0
AN:
60378
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:1
Apr 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 24 of the APC protein (p.Arg24Gln). This variant is present in population databases (no rsID available, gnomAD no frequency). This variant has not been reported in the literature in individuals affected with APC-related conditions. ClinVar contains an entry for this variant (Variation ID: 236642). 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 with a negative predictive value of 95%. 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. -

Classic or attenuated familial adenomatous polyposis Uncertain:1
Jun 26, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces arginine with glutamine at codon 24 of the APC protein. Computational prediction tool suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <=0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with hereditary cancer in the literature. This variant has been identified in 1/251240 chromosomes 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. -

not provided Uncertain:1
Oct 08, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 18199528) -

Hereditary cancer-predisposing syndrome Uncertain:1
Mar 28, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R24Q variant (also known as c.71G>A), located in coding exon 1 of the APC gene, results from a G to A substitution at nucleotide position 71. The arginine at codon 24 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, in silico predictors for this gene do not accurately predict pathogenicity. Based on the available evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.49
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Uncertain
0.13
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.44
T;D;D;T
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.92
D;.;D;D
M_CAP
Benign
0.022
T
MetaRNN
Uncertain
0.57
D;D;D;D
MetaSVM
Benign
-0.92
T
MutationAssessor
Uncertain
2.0
.;M;M;.
PhyloP100
9.5
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-3.7
D;D;D;D
REVEL
Uncertain
0.42
Sift
Uncertain
0.0040
D;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D
Polyphen
1.0
.;D;D;.
Vest4
0.81, 0.85
MutPred
0.18
Gain of relative solvent accessibility (P = 0.09);Gain of relative solvent accessibility (P = 0.09);Gain of relative solvent accessibility (P = 0.09);Gain of relative solvent accessibility (P = 0.09);
MVP
0.87
ClinPred
0.97
D
GERP RS
5.7
Varity_R
0.82
gMVP
0.37
Mutation Taster
=55/45
polymorphism

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

Other links and lift over

dbSNP: rs878853469; hg19: chr5-112090658; COSMIC: COSV99074983; API