NM_005359.6:c.1403A>G

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 5P and 2B. PM1PM2PP2BP4_Moderate

The NM_005359.6(SMAD4):c.1403A>G(p.Asn468Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000656 in 152,336 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 Uncertain significance (★★).

Frequency

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

Consequence

SMAD4
NM_005359.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.34

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 links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM1

In a domain MH2 (size 229) in uniprot entity SMAD4_HUMAN there are 74 pathogenic changes around while only 6 benign (93%) in NM_005359.6

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in the SMAD4 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 36 curated pathogenic missense variants (we use a threshold of 10). The gene has 52 curated benign missense variants. Gene score misZ: 4.1308 (above the threshold of 3.09). Trascript score misZ: 4.9346 (above the threshold of 3.09). GenCC associations: The gene is linked to familial thoracic aortic aneurysm and aortic dissection, generalized juvenile polyposis/juvenile polyposis coli, hereditary hemorrhagic telangiectasia, Myhre syndrome, pulmonary arterial hypertension, juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome, juvenile polyposis syndrome.

BP4

Computational evidence support a benign effect (MetaRNN=0.24964541).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMAD4	NM_005359.6 link	c.1403A>G	p.Asn468Ser	missense_variant	Exon 11 of 12	ENST00000342988.8	NP_005350.1	Q13485A0A024R274
SMAD4	NM_001407041.1 link	c.1403A>G	p.Asn468Ser	missense_variant	Exon 11 of 12		NP_001393970.1
SMAD4	NM_001407042.1 link	c.1403A>G	p.Asn468Ser	missense_variant	Exon 11 of 12		NP_001393971.1
SMAD4	NR_176265.1 link	n.1941A>G		non_coding_transcript_exon_variant	Exon 11 of 13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMAD4	ENST00000342988.8 link	c.1403A>G	p.Asn468Ser	missense_variant	Exon 11 of 12	5	NM_005359.6	ENSP00000341551.3		Q13485

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

Cov.:

GnomAD4 genome

AF:

0.00000656

AC:

AN:

152336

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74492

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000653

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection

Uncertain:1

Apr 10, 2017

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.N468S variant (also known as c.1403A>G), located in coding exon 10 of the SMAD4 gene, results from an A to G substitution at nucleotide position 1403. The asparagine at codon 468 is replaced by serine, 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. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Feb 24, 2020

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces asparagine with serine at codon 468 of the SMAD4 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, 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 not been identified 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. -

Juvenile polyposis syndrome

Uncertain:1

Oct 23, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is present in population databases (rs569981255, gnomAD 0.003%). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 468 of the SMAD4 protein (p.Asn468Ser). This variant has not been reported in the literature in individuals affected with SMAD4-related conditions. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 486453). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Uncertain

0.043

BayesDel_noAF

Benign

-0.090

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.90

D;D;D;.

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.56

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.93

.;D;D;D

M_CAP

Benign

0.067

MetaRNN

Benign

0.25

T;T;T;T

MetaSVM

Uncertain

0.55

MutationAssessor

Benign

-0.27

N;N;.;.

PrimateAI

Pathogenic

0.82

PROVEAN

Uncertain

-2.5

N;N;.;.

REVEL

Uncertain

0.50

Sift

Benign

0.56

T;T;.;.

Sift4G

Benign

0.45

T;T;T;T

Polyphen

0.99

D;D;.;.

Vest4

0.49

MutPred

0.38

Gain of glycosylation at N468 (P = 4e-04);Gain of glycosylation at N468 (P = 4e-04);.;.;

MVP

0.88

MPC

1.3

ClinPred

0.51

GERP RS

5.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.20

gMVP

0.65

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over