15-67181315-G-C

Variant names:

• chr15-67181315-G-C
• rs863223737
• NM_005902.4:c.733G>C

Variant summary

Our verdict is Pathogenic. The variant received 26 ACMG points: 26P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_005902.4(SMAD3):​c.733G>C​(p.Gly245Arg) 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. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G245W) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMAD3 NM_005902.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 9.87
• Publications: 10 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: Pathogenic. The variant received 26 ACMG points.

• PS1: Transcript NM_005902.4 (SMAD3) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 15 uncertain in NM_005902.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr15-67181315-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3776765.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant 15-67181315-G-C is Pathogenic according to our data. Variant chr15-67181315-G-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 520179.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005902.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD3	NM_005902.4	MANE Select	c.733G>C	p.Gly245Arg	missense	Exon 6 of 9	NP_005893.1
	SMAD3	NM_001407011.1		c.733G>C	p.Gly245Arg	missense	Exon 6 of 10	NP_001393940.1
	SMAD3	NM_001145103.2		c.601G>C	p.Gly201Arg	missense	Exon 6 of 9	NP_001138575.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD3	ENST00000327367.9	TSL:1 MANE Select	c.733G>C	p.Gly245Arg	missense	Exon 6 of 9	ENSP00000332973.4
	SMAD3	ENST00000439724.7	TSL:1	c.601G>C	p.Gly201Arg	missense	Exon 6 of 9	ENSP00000401133.3
	SMAD3	ENST00000540846.6	TSL:1	c.418G>C	p.Gly140Arg	missense	Exon 6 of 9	ENSP00000437757.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:2

Dec 19, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 245 of the SMAD3 protein (p.Gly245Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with clinical features of SMAD3-related conditions (PMID: 24804794, 29444731; Invitae). ClinVar contains an entry for this variant (Variation ID: 520179). Advanced modeling performed at Invitae incorporating data from internal and/or published experimental studies (Invitae) indicates that this missense variant is expected to disrupt SMAD3 function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic.

Aug 06, 2019

Ambry Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G245R variant (also known as c.733G>C), located in coding exon 6 of the SMAD3 gene, results from a G to C substitution at nucleotide position 733. The glycine at codon 245 is replaced by arginine, an amino acid with dissimilar properties. This alteration was previously reported in a nonsyndromic pediatric patient with a dilated aorta (Arroyave J et al. Cardiol Young, 2018;28:765-767). Internal structural analysis indicates that this variant causes a significant decrease in SMAD3 structural stability (Qin BY et al. Genes Dev. 2002 Aug;16(15):1950-63; Ambry internal data). A likely pathogenic alteration resulting in the same amino acid change (c.733G>A p.G245R) has also been described (Aubart M. PLoS ONE 2014; 9(5):e96387). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	1.0	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.85	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	4.1	H
PhyloP100		9.9
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-7.7	D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.93		Gain of sheet (P = 0.1539)
MVP		0.99
MPC		2.6
ClinPred		1.0	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.97
gMVP		0.90
Mutation Taster		=0/100	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs863223737; hg19: chr15-67473653;