rs377026877

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4BS2

The NM_005902.4(SMAD3):​c.440C>T​(p.Pro147Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000229 in 1,614,084 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 (★★). Synonymous variant affecting the same amino acid position (i.e. P147P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

SMAD3
NM_005902.4 missense

Scores

2
6
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 6.04

Publications

1 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.36970913).
BS2
High AC in GnomAd4 at 7 AD gene.

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
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SMAD3
NM_005902.4
MANE Select
c.440C>Tp.Pro147Leu
missense
Exon 3 of 9NP_005893.1
SMAD3
NM_001407011.1
c.440C>Tp.Pro147Leu
missense
Exon 3 of 10NP_001393940.1
SMAD3
NM_001145103.2
c.308C>Tp.Pro103Leu
missense
Exon 3 of 9NP_001138575.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SMAD3
ENST00000327367.9
TSL:1 MANE Select
c.440C>Tp.Pro147Leu
missense
Exon 3 of 9ENSP00000332973.4
SMAD3
ENST00000439724.7
TSL:1
c.308C>Tp.Pro103Leu
missense
Exon 3 of 9ENSP00000401133.3
SMAD3
ENST00000540846.6
TSL:1
c.125C>Tp.Pro42Leu
missense
Exon 3 of 9ENSP00000437757.2

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152204
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000941
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000318
AC:
8
AN:
251408
AF XY:
0.0000294
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000205
AC:
30
AN:
1461880
Hom.:
0
Cov.:
34
AF XY:
0.0000124
AC XY:
9
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000224
AC:
1
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.0000374
AC:
2
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000216
AC:
24
AN:
1112006
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
2
4
7
9
11
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152204
Hom.:
0
Cov.:
33
AF XY:
0.0000403
AC XY:
3
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.0000941
AC:
1
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.454
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000950
Hom.:
0
Bravo
AF:
0.0000378
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000494
AC:
6
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:4
Oct 26, 2021
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Apr 26, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.P147L variant (also known as c.440C>T), located in coding exon 3 of the SMAD3 gene, results from a C to T substitution at nucleotide position 440. The proline at codon 147 is replaced by leucine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Jul 26, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces proline with leucine at codon 147 of the SMAD3 protein. Computational prediction tools indicate that this variant has a neutral impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with SMAD3-related disorders in the literature. This variant has been identified in 9/282800 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.

Jan 31, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 147 of the SMAD3 protein (p.Pro147Leu). This variant is present in population databases (rs377026877, gnomAD 0.005%). 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: 196428). Invitae Evidence Modeling incorporating data from in vitro experimental studies (internal data) indicates that this missense variant is not expected to disrupt SMAD3 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.

not provided Uncertain:2
Sep 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

SMAD3: PP2, PP3

May 14, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not specified Uncertain:1
Jul 07, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: SMAD3 c.440C>T (p.Pro147Leu) results in a non-conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 3.2e-05 in 251408 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.440C>T in individuals affected with Thoracic Aortic Aneurysms And Dissections and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 196428). Based on the evidence outlined above, the variant was classified as uncertain significance.

Connective tissue disorder Uncertain:1
Nov 01, 2016
Center for Human Genetics, Inc, Center for Human Genetics, Inc
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Aneurysm-osteoarthritis syndrome Uncertain:1
Sep 23, 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 proline with leucine at codon 147 of the SMAD3 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 cardiovascular disorders in the literature. This variant has been identified in 9/282800 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.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Uncertain
0.16
D
BayesDel_noAF
Pathogenic
0.17
CADD
Uncertain
25
DANN
Benign
0.97
DEOGEN2
Benign
0.41
T
Eigen
Benign
-0.18
Eigen_PC
Benign
0.025
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Uncertain
0.92
D
M_CAP
Uncertain
0.15
D
MetaRNN
Benign
0.37
T
MetaSVM
Uncertain
0.39
D
MutationAssessor
Benign
0.87
L
PhyloP100
6.0
PrimateAI
Pathogenic
0.84
D
PROVEAN
Benign
-0.69
N
REVEL
Uncertain
0.44
Sift
Benign
0.33
T
Sift4G
Benign
0.49
T
Polyphen
0.0
B
Vest4
0.54
MVP
0.94
MPC
1.2
ClinPred
0.13
T
GERP RS
4.7
Varity_R
0.43
gMVP
0.67
Mutation Taster
=10/90
disease causing

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

Other links and lift over

dbSNP: rs377026877; hg19: chr15-67457630; COSMIC: COSV99046571; COSMIC: COSV99046571; API