chr18-51058155-A-G

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_005359.6(SMAD4):​c.698A>G​(p.His233Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000062 in 1,614,072 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. 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. H233N) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

SMAD4
NM_005359.6 missense

Scores

5
14

Clinical Significance

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

Conservation

PhyloP100: 4.12

Publications

0 publications found
Variant links:
Genes affected
SMAD4 (HGNC:6770): (SMAD family member 4) This gene encodes a member of the Smad family of signal transduction proteins. Smad proteins are phosphorylated and activated by transmembrane serine-threonine receptor kinases in response to transforming growth factor (TGF)-beta signaling. The product of this gene forms homomeric complexes and heteromeric complexes with other activated Smad proteins, which then accumulate in the nucleus and regulate the transcription of target genes. This protein binds to DNA and recognizes an 8-bp palindromic sequence (GTCTAGAC) called the Smad-binding element (SBE). The protein acts as a tumor suppressor and inhibits epithelial cell proliferation. It may also have an inhibitory effect on tumors by reducing angiogenesis and increasing blood vessel hyperpermeability. The encoded protein is a crucial component of the bone morphogenetic protein signaling pathway. The Smad proteins are subject to complex regulation by post-translational modifications. Mutations or deletions in this gene have been shown to result in pancreatic cancer, juvenile polyposis syndrome, and hereditary hemorrhagic telangiectasia syndrome. [provided by RefSeq, May 2022]
SMAD4 Gene-Disease associations (from GenCC):
  • juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, G2P, PanelApp Australia
  • Myhre syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • generalized juvenile polyposis/juvenile polyposis coli
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
  • juvenile polyposis syndrome
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • hereditary hemorrhagic telangiectasia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • pulmonary arterial hypertension
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.23085764).
BS2
High AC in GnomAdExome4 at 9 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMAD4NM_005359.6 linkc.698A>G p.His233Arg missense_variant Exon 6 of 12 ENST00000342988.8 NP_005350.1 Q13485A0A024R274

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMAD4ENST00000342988.8 linkc.698A>G p.His233Arg missense_variant Exon 6 of 12 5 NM_005359.6 ENSP00000341551.3 Q13485
ENSG00000267699ENST00000590722.2 linkn.*874A>G downstream_gene_variant 2 ENSP00000465737.1 E7EUB6

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152236
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000616
AC:
9
AN:
1461836
Hom.:
0
Cov.:
33
AF XY:
0.00000550
AC XY:
4
AN XY:
727222
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:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000809
AC:
9
AN:
1111958
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
1
2
4
5
6
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
AF:
0.00000657
AC:
1
AN:
152236
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74374
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Mar 30, 2018
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: SMAD4 c.698A>G (p.His233Arg) 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 was absent in 121270 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.698A>G in individuals affected with Juvenile Polyposis Syndrome 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. -

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
Mar 24, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.H233R variant (also known as c.698A>G), located in coding exon 5 of the SMAD4 gene, results from an A to G substitution at nucleotide position 698. The histidine at codon 233 is replaced by arginine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
Apr 16, 2018
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The SMAD4 c.698A>G; p.His233Arg variant, to our knowledge, is not reported in the medical literature or gene specific databases. This variant is also absent from the general population databases (1000 Genomes Project, Exome Variant Server, and Genome Aggregation Database), indicating it is not a common polymorphism. The histidine at codon 233 is highly conserved, but computational analyses (SIFT, PolyPhen-2) predict that this variant is tolerated. However, given the lack of clinical and functional data, the significance of the p.His233Arg variant is uncertain at this time. -

Juvenile polyposis syndrome Uncertain:1
Jun 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 233 of the SMAD4 protein (p.His233Arg). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SMAD4-related conditions. ClinVar contains an entry for this variant (Variation ID: 529909). 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 SMAD4 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Uncertain
0.16
D
BayesDel_noAF
Uncertain
-0.010
CADD
Benign
19
DANN
Benign
0.97
DEOGEN2
Uncertain
0.59
D;D
Eigen
Benign
-0.10
Eigen_PC
Benign
0.12
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.79
.;T
M_CAP
Benign
0.042
D
MetaRNN
Benign
0.23
T;T
MetaSVM
Benign
-0.83
T
MutationAssessor
Benign
2.0
M;M
PhyloP100
4.1
PrimateAI
Uncertain
0.65
T
PROVEAN
Benign
-1.6
N;N
REVEL
Benign
0.25
Sift
Benign
0.57
T;T
Sift4G
Benign
0.55
T;T
Polyphen
0.012
B;B
Vest4
0.39
MutPred
0.24
Gain of phosphorylation at S234 (P = 0.0916);Gain of phosphorylation at S234 (P = 0.0916);
MVP
0.94
MPC
0.56
ClinPred
0.32
T
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.14
gMVP
0.35
Mutation Taster
=85/15
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: rs1555685910; hg19: chr18-48584525; API