rs1057519259

Variant names:

• chr18-51054789-A-G
• rs1057519259
• NM_005359.6:c.463A>G

Your query was ambiguous. Multiple possible variants found:

• chr18-51054789-A-G
• chr18-51054789-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_005359.6(SMAD4):​c.463A>G​(p.Ser155Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000208 in 1,441,718 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SMAD4 NM_005359.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:5
• Conservation: PhyloP100: 4.37

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]

ENSG00000267699 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• 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=0.16839966).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMAD4	NM_005359.6	c.463A>G	p.Ser155Gly	missense_variant	Exon 5 of 12	ENST00000342988.8	NP_005350.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMAD4	ENST00000342988.8	c.463A>G	p.Ser155Gly	missense_variant	Exon 5 of 12	5	NM_005359.6	ENSP00000341551.3
ENSG00000267699	ENST00000590722.2	n.*639A>G		non_coding_transcript_exon_variant	Exon 8 of 9	2		ENSP00000465737.1
ENSG00000267699	ENST00000590722.2	n.*639A>G		3_prime_UTR_variant	Exon 8 of 9	2		ENSP00000465737.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251376 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135864

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000208 AC: 3 AN: 1441718 Hom.: 0 Cov.: 29 AF XY: 0.00000278 AC XY: 2 AN XY: 718410

Gnomad4 AFR exome AF: 0.0000302

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.14e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Uncertain:2

Jan 27, 2016

Knight Diagnostic Laboratories, Oregon Health and Sciences University

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Aug 06, 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 serine with glycine at codon 155 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 not been reported in individuals affected with SMAD4-related disorders in the literature. This variant has been identified in 1/251376 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. -

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Dec 26, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S155G variant (also known as c.463A>G), located in coding exon 4 of the SMAD4 gene, results from an A to G substitution at nucleotide position 463. The serine at codon 155 is replaced by glycine, an amino acid with similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Hereditary cancer-predisposing syndrome Uncertain:1

Oct 19, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces serine with glycine at codon 155 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 not been reported in individuals affected with SMAD4-related disorders in the literature. This variant has been identified in 1/251376 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. -

Juvenile polyposis syndrome Uncertain:1

Aug 15, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with glycine, which is neutral and non-polar, at codon 155 of the SMAD4 protein (p.Ser155Gly). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This missense change has been observed in individual(s) with vascular anomalies (PMID: 28655553). ClinVar contains an entry for this variant (Variation ID: 374977). 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 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	0.057
BayesDel_addAF	Benign	-0.0035	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	20
DANN	Benign	0.69
DEOGEN2	Benign	0.36	T;T;T
Eigen	Benign	-0.47
Eigen_PC	Benign	-0.21
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.69	.;T;T
M_CAP	Uncertain	0.16	D
MetaRNN	Benign	0.17	T;T;T
MetaSVM	Uncertain	0.15	D
MutationAssessor	Benign	-0.35	N;N;.
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-0.73	N;N;.
REVEL	Uncertain	0.48
Sift	Benign	0.54	T;T;.
Sift4G	Benign	0.44	T;T;T
Polyphen		0.0	B;B;.
Vest4		0.20
MutPred		0.24		Gain of glycosylation at S154 (P = 0.0338);Gain of glycosylation at S154 (P = 0.0338);Gain of glycosylation at S154 (P = 0.0338);
MVP		0.60
MPC		0.42
ClinPred		0.14	T
GERP RS		5.8
Varity_R		0.095
gMVP		0.41

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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

Other links and lift over

dbSNP: rs1057519259; hg19: chr18-48581159;