18-51078416-A-G

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_005359.6(SMAD4):​c.1608A>G​(p.Leu536Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,102 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 Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. L536L) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

SMAD4
NM_005359.6 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:10

Conservation

PhyloP100: -0.144

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp, G2P, PanelApp Australia
  • Myhre syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • generalized juvenile polyposis/juvenile polyposis coli
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
  • juvenile polyposis syndrome
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • hereditary hemorrhagic telangiectasia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • pulmonary arterial hypertension
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.59).
BP6
Variant 18-51078416-A-G is Benign according to our data. Variant chr18-51078416-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 460542.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.144 with no splicing effect.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.0000394 (6/152222) while in subpopulation AFR AF = 0.000145 (6/41462). AF 95% confidence interval is 0.0000628. There are 0 homozygotes in GnomAd4. There are 3 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 6 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMAD4NM_005359.6 linkc.1608A>G p.Leu536Leu synonymous_variant Exon 12 of 12 ENST00000342988.8 NP_005350.1 Q13485A0A024R274
SMAD4NM_001407041.1 linkc.1608A>G p.Leu536Leu synonymous_variant Exon 12 of 12 NP_001393970.1
SMAD4NM_001407042.1 linkc.1608A>G p.Leu536Leu synonymous_variant Exon 12 of 12 NP_001393971.1
SMAD4NR_176265.1 linkn.2259A>G non_coding_transcript_exon_variant Exon 13 of 13

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMAD4ENST00000342988.8 linkc.1608A>G p.Leu536Leu synonymous_variant Exon 12 of 12 5 NM_005359.6 ENSP00000341551.3 Q13485

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152222
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000145
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:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251440
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.000123
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461880
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727238
show subpopulations
African (AFR)
AF:
0.000149
AC:
5
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000394
AC:
6
AN:
152222
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74372
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41462
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.517
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000557
Hom.:
0
Bravo
AF:
0.0000567

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:2
Oct 22, 2021
Sema4, Sema4
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Mar 17, 2016
Color Diagnostics, LLC DBA Color Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Benign:2
Feb 05, 2024
All of Us Research Program, National Institutes of Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 24, 2025
Myriad Genetics, Inc.
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is considered benign. This variant is a silent/synonymous amino acid change and it is not expected to impact splicing. -

not specified Benign:1
Sep 03, 2019
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SMAD4-related disorder Benign:1
Jul 01, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Familial thoracic aortic aneurysm and aortic dissection Benign:1
Aug 14, 2019
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
Nov 22, 2016
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

not provided Benign:1
May 17, 2021
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at a significant frequency in large population cohorts (Lek et al., 2016); This variant is associated with the following publications: (PMID: 26343386) -

Juvenile polyposis syndrome Benign:1
Dec 26, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.59
CADD
Benign
1.4
DANN
Benign
0.61
PhyloP100
-0.14
Mutation Taster
=93/7
polymorphism

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: rs753128184; hg19: chr18-48604786; API