rs876659967

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2PP2BP4

The NM_005359.6(SMAD4):c.736C>A(p.Pro246Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,854 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).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

SMAD4
NM_005359.6 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 5.84

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:

SMAD4 (HGNC:):

SMAD4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SMAD4. . Gene score misZ 4.1308 (greater than the threshold 3.09). Trascript score misZ 4.9346 (greater than threshold 3.09). GenCC has associacion of gene with 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=0.3655786).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SMAD4	NM_005359.6 linkuse as main transcript	c.736C>A	p.Pro246Thr	missense_variant	6/12	ENST00000342988.8	NP_005350.1	Q13485A0A024R274

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SMAD4	ENST00000342988.8 linkuse as main transcript	c.736C>A	p.Pro246Thr	missense_variant	6/12	5	NM_005359.6	ENSP00000341551.3		Q13485
ENSG00000267699	ENST00000590722.2 linkuse as main transcript	n.*912C>A		downstream_gene_variant		2		ENSP00000465737.1		E7EUB6

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000795

AC:

AN:

251442

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135892

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461854

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727236

show subpopulations

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:9Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Jul 20, 2024	This missense variant replaces proline with threonine at codon 246 of the SMAD4 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 been reported in an individual affected with aortic dissection (PMID: 30809044). This variant has been identified in 2/251442 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. -

Myhre syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Early age onset of sporadic thoracic aortic dissections

Uncertain:1

Uncertain significance, no assertion criteria provided

research

University of Washington Center for Mendelian Genomics, University of Washington

- -

Heritable Thoracic Aortic Disease

Uncertain:1

Uncertain significance, criteria provided, single submitter

research

Department of Internal Medicine, The University of Texas McGovern Medical School, The University of Texas Health Science Center at Houston

Apr 01, 2018

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 19, 2017

- -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Apr 04, 2019

- -

Generalized juvenile polyposis/juvenile polyposis coli

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

Juvenile polyposis syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 23, 2023

This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 246 of the SMAD4 protein (p.Pro246Thr). This variant is present in population databases (no rsID available, gnomAD 0.002%). This missense change has been observed in individual(s) with aortic dissection (PMID: 30809044). ClinVar contains an entry for this variant (Variation ID: 232751). 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%. Experimental studies have shown that this missense change does not substantially affect SMAD4 function (PMID: 30809044). 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. -

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

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

May 31, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.056

BayesDel_addAF

Uncertain

0.029

BayesDel_noAF

Benign

-0.18

CADD

Uncertain

DANN

Uncertain

0.98

DEOGEN2

Uncertain

0.65

D;D

Eigen

Benign

0.088

Eigen_PC

Uncertain

0.30

FATHMM_MKL

Uncertain

0.96

LIST_S2

Benign

0.83

.;T

M_CAP

Benign

0.028

MetaRNN

Benign

0.37

T;T

MetaSVM

Benign

-0.85

MutationAssessor

Benign

1.4

L;L

PrimateAI

Uncertain

0.67

PROVEAN

Benign

-1.9

N;N

REVEL

Benign

0.21

Sift

Benign

0.14

T;T

Sift4G

Uncertain

0.046

D;D

Polyphen

0.18

B;B

Vest4

0.56

MutPred

0.24

Gain of relative solvent accessibility (P = 0.0166);Gain of relative solvent accessibility (P = 0.0166);

MVP

0.62

MPC

0.52

ClinPred

0.21

GERP RS

5.8

Varity_R

0.11

gMVP

0.40

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