5-112838077-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM1BP4_Moderate

The NM_000038.6(APC):​c.2483C>T​(p.Thr828Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000103 in 1,461,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T828A) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

APC
NM_000038.6 missense

Scores

1
10
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:9B:1

Conservation

PhyloP100: 3.85

Publications

1 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 0 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 37 uncertain in NM_000038.6
BP4
Computational evidence support a benign effect (MetaRNN=0.25747365).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
APCNM_000038.6 linkc.2483C>T p.Thr828Ile missense_variant Exon 16 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.2483C>T p.Thr828Ile missense_variant Exon 16 of 16 5 NM_000038.6 ENSP00000257430.4 P25054-1
ENSG00000258864ENST00000520401.1 linkn.228+9105C>T intron_variant Intron 3 of 7 3 ENSP00000454861.1 H3BNH8

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251040
AF XY:
0.00000737
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461878
Hom.:
0
Cov.:
33
AF XY:
0.00000550
AC XY:
4
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53408
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000117
AC:
13
AN:
1112010
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.472
Heterozygous variant carriers
0
1
2
2
3
4
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
Bravo
AF:
0.0000151
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:9Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Familial adenomatous polyposis 1 Uncertain:4
Feb 16, 2023
Myriad Genetics, Inc.
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is classified as a variant of uncertain significance as there is insufficient evidence to determine its impact on protein function and/or cancer risk. -

Nov 18, 2015
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jan 09, 2024
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 828 of the APC protein (p.Thr828Ile). This variant is present in population databases (rs786203696, gnomAD 0.0009%). 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: 187390). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) 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. -

not provided Uncertain:2
Feb 13, 2019
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 05, 2023
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; Observed in an individual with breast cancer (PMID: 25186627); This variant is associated with the following publications: (PMID: 36118902, 30122538, 25186627) -

Hereditary cancer-predisposing syndrome Uncertain:1Benign:1
Mar 14, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.T828I variant (also known as c.2483C>T), located in coding exon 15 of the APC gene, results from a C to T substitution at nucleotide position 2483. The threonine at codon 828 is replaced by isoleucine, an amino acid with similar properties. This alteration was detected on a 25-gene panel test in a woman of Western/Northern European ancestry who was diagnosed with breast cancer before age 50 (Tung N et al. Cancer, 2015 Jan;121:25-33). 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. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Feb 10, 2025
Color Diagnostics, LLC DBA Color Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
May 03, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: APC c.2483C>T (p.Thr828Ile) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251040 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2483C>T has been reported in the literature in an individual affected with breast cancer undergoing multigene panel testing (example Tung_2015). This report does not provide unequivocal conclusions about association of the variant with Familial Adenomatous Polyposis. At-least one co-occurrence with another pathogenic variant has been observed at our laboratory (PALB2 c.196C>T, p.Gln66*), providing supporting evidence for a benign role. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Classic or attenuated familial adenomatous polyposis Uncertain:1
Apr 10, 2024
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 threonine with isoleucine at codon 828 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 been reported in an individual affected with breast cancer (PMID: 25186627).This variant has been identified in 1/251040 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.26
BayesDel_addAF
Uncertain
0.070
D
BayesDel_noAF
Benign
-0.14
CADD
Benign
23
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.87
.;D;D;D
Eigen
Benign
0.17
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.93
D;.;D;D
M_CAP
Benign
0.023
T
MetaRNN
Benign
0.26
T;T;T;T
MetaSVM
Uncertain
0.11
D
MutationAssessor
Benign
1.6
.;L;L;.
PhyloP100
3.9
PrimateAI
Uncertain
0.64
T
PROVEAN
Benign
-2.3
N;D;D;N
REVEL
Uncertain
0.33
Sift
Uncertain
0.0080
D;D;D;D
Sift4G
Uncertain
0.036
D;T;T;D
Polyphen
0.37
.;B;B;.
Vest4
0.64, 0.50
MutPred
0.36
.;Loss of glycosylation at T828 (P = 0.0224);Loss of glycosylation at T828 (P = 0.0224);Loss of glycosylation at T828 (P = 0.0224);
MVP
0.81
ClinPred
0.47
T
GERP RS
5.3
Varity_R
0.26
gMVP
0.66
Mutation Taster
=74/26
polymorphism

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

Other links and lift over

dbSNP: rs786203696; hg19: chr5-112173774; API