rs1060500767

Variant names:

• chr15-67184762-G-A
• rs1060500767
• NM_005902.4:c.907G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_005902.4(SMAD3):​c.907G>A​(p.Val303Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. V303D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMAD3 NM_005902.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.77
• Publications: 2 publications found

Genes affected

SMAD3 (HGNC:6769): (SMAD family member 3) The SMAD family of proteins are a group of intracellular signal transducer proteins similar to the gene products of the Drosophila gene 'mothers against decapentaplegic' (Mad) and the C. elegans gene Sma. The SMAD3 protein functions in the transforming growth factor-beta signaling pathway, and transmits signals from the cell surface to the nucleus, regulating gene activity and cell proliferation. This protein forms a complex with other SMAD proteins and binds DNA, functioning both as a transcription factor and tumor suppressor. Mutations in this gene are associated with aneurysms-osteoarthritis syndrome and Loeys-Dietz Syndrome 3. [provided by RefSeq, May 2022]

SMAD3 Gene-Disease associations (from GenCC):

• aneurysm-osteoarthritis syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Genomics England PanelApp, Orphanet, G2P, ClinGen, Labcorp Genetics (formerly Invitae)
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.822

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMAD3	NM_005902.4	c.907G>A	p.Val303Ile	missense_variant	Exon 7 of 9	ENST00000327367.9	NP_005893.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMAD3	ENST00000327367.9	c.907G>A	p.Val303Ile	missense_variant	Exon 7 of 9	1	NM_005902.4	ENSP00000332973.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Oct 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 303 of the SMAD3 protein (p.Val303Ile). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SMAD3-related conditions. ClinVar contains an entry for this variant (Variation ID: 405562). Invitae Evidence Modeling incorporating data from in vitro experimental studies (internal data) indicates that this missense variant is expected to disrupt SMAD3 function with a positive 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	Pathogenic	0.63
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.84	D;.;.;.;.
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D
M_CAP	Uncertain	0.27	D
MetaRNN	Pathogenic	0.82	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.1	M;.;.;.;.
PhyloP100		9.8
PrimateAI	Pathogenic	0.81	D
PROVEAN	Benign	-0.89	N;N;N;N;N
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0020	D;D;D;D;D
Sift4G	Uncertain	0.047	D;T;T;T;D
Polyphen		0.79	P;.;.;.;.
Vest4		0.77
MutPred		0.71		Loss of sheet (P = 0.302);.;.;.;.;
MVP		0.93
MPC		1.9
ClinPred		0.94	D
GERP RS		5.3
PromoterAI		-0.0054	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.63
gMVP		0.58
Mutation Taster		=42/58	disease causing

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

Other links and lift over

dbSNP: rs1060500767; hg19: chr15-67477100;