rs145988618

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_005359.6(SMAD4):​c.354G>A​(p.Ala118Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00372 in 1,613,918 control chromosomes in the GnomAD database, including 17 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0038 ( 17 hom. )

Consequence

SMAD4
NM_005359.6 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:24

Conservation

PhyloP100: -0.204
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]

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.54).
BP6
Variant 18-51048790-G-A is Benign according to our data. Variant chr18-51048790-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 24799.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr18-51048790-G-A is described in Lovd as [Benign]. Variant chr18-51048790-G-A is described in Lovd as [Likely_benign].
BP7
Synonymous conserved (PhyloP=-0.204 with no splicing effect.
BS1
Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00256 (390/152224) while in subpopulation NFE AF= 0.00428 (291/68024). AF 95% confidence interval is 0.00387. There are 0 homozygotes in gnomad4. There are 188 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
BS2
High AC in GnomAd4 at 390 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMAD4NM_005359.6 linkc.354G>A p.Ala118Ala synonymous_variant Exon 3 of 12 ENST00000342988.8 NP_005350.1 Q13485A0A024R274

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMAD4ENST00000342988.8 linkc.354G>A p.Ala118Ala synonymous_variant Exon 3 of 12 5 NM_005359.6 ENSP00000341551.3 Q13485
ENSG00000267699ENST00000590722.2 linkn.*377G>A non_coding_transcript_exon_variant Exon 4 of 9 2 ENSP00000465737.1 E7EUB6
ENSG00000267699ENST00000590722.2 linkn.*377G>A 3_prime_UTR_variant Exon 4 of 9 2 ENSP00000465737.1 E7EUB6

Frequencies

GnomAD3 genomes
AF:
0.00256
AC:
390
AN:
152108
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000990
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00124
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00303
Gnomad MID
AF:
0.00318
Gnomad NFE
AF:
0.00428
Gnomad OTH
AF:
0.00287
GnomAD3 exomes
AF:
0.00276
AC:
693
AN:
251432
Hom.:
3
AF XY:
0.00262
AC XY:
356
AN XY:
135890
show subpopulations
Gnomad AFR exome
AF:
0.00111
Gnomad AMR exome
AF:
0.000636
Gnomad ASJ exome
AF:
0.000298
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000131
Gnomad FIN exome
AF:
0.00513
Gnomad NFE exome
AF:
0.00459
Gnomad OTH exome
AF:
0.00212
GnomAD4 exome
AF:
0.00384
AC:
5613
AN:
1461694
Hom.:
17
Cov.:
32
AF XY:
0.00374
AC XY:
2716
AN XY:
727174
show subpopulations
Gnomad4 AFR exome
AF:
0.00108
Gnomad4 AMR exome
AF:
0.000581
Gnomad4 ASJ exome
AF:
0.000344
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000128
Gnomad4 FIN exome
AF:
0.00470
Gnomad4 NFE exome
AF:
0.00460
Gnomad4 OTH exome
AF:
0.00265
GnomAD4 genome
AF:
0.00256
AC:
390
AN:
152224
Hom.:
0
Cov.:
33
AF XY:
0.00253
AC XY:
188
AN XY:
74426
show subpopulations
Gnomad4 AFR
AF:
0.000987
Gnomad4 AMR
AF:
0.00124
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00303
Gnomad4 NFE
AF:
0.00428
Gnomad4 OTH
AF:
0.00284
Alfa
AF:
0.00340
Hom.:
1
Bravo
AF:
0.00218
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.00354
EpiControl
AF:
0.00338

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:24
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:7
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jul 15, 2016
PreventionGenetics, part of Exact Sciences
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Nov 04, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Mar 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

SMAD4: BP4, BP7, BS1, BS2 -

Jul 08, 2022
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not specified Benign:6
-
Clinical Genetics, Academic Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Genome Diagnostics Laboratory, Amsterdam University Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 08, 2014
GeneDx
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

Jul 25, 2018
Genetic Services Laboratory, University of Chicago
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Mayo Clinic Laboratories, Mayo Clinic
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Mar 04, 2025
Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome Benign:4
Mar 23, 2020
Sema4, Sema4
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: curation

- -

Mar 09, 2016
Color Diagnostics, LLC DBA Color Health
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Dec 08, 2017
True Health Diagnostics
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Nov 13, 2024
Molecular Diagnostics Laboratory, Catalan Institute of Oncology
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

BS2_Supporting, BP4, BP7 c.354G>A located in exon 11 of the SMAD4 gene affects a non-conserved nucleotide, resulting in no amino acid change, p.(Ala464=) (BP7). This variant allele was found in 540/118134 alleles (3 homozygotes), with a filtered allele frequency of 0.41% at 99% confidence, within the European (non-Finnish) population in the gnomAD v2.1.1 database (non-cancer data set) (BS2_Supporting). The SpliceAI algorithm predicts no significant impact on splicing (BP4). To our knowledge, no well-established functional studies have been reported for this variant. This variant has been reported in controls and patients affected with multiple adenomatous polyposis, early-onset colorectal cancer, juvenile polyposis syndrome, endometrial cancer and AFAP (PMID: 22875147, 16436638, internal data). It has been reported in the ClinVar database (12x benign and 10x likely benign) and in the LOVD database (2x benign and 3x likely benign). Based on currently available information, the variant c.354G>A should be considered a likely benign variant. -

Myhre syndrome Benign:2
Feb 01, 2025
KCCC/NGS Laboratory, Kuwait Cancer Control Center
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Carcinoma of colon Benign:1
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

The SMAD4 p.Ala118= variant was identified in 1 of 140 proband chromosomes (frequency: 0.007) from individuals or families with Juvenile polyposis syndrome (Pyatt 2006). The variant was also identified in dbSNP (ID: rs145988618) as "With other allele", ClinVar (classified as benign by Invitae, GeneDx, and ARUP; as likely benign by 7 submitters), Cosmic (2X in large intestine tissue), LOVD 3.0 (4x as benign or likely benign), and in ARUP Laboratories (as benign). The variant was identified in control databases in 768 of 277174 chromosomes (3 homozygous) at a frequency of 0.003 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: African in 23 of 24032 chromosomes (freq: 0.0009), Other in 13 of 6462 chromosomes (freq: 0.002), Latino in 21 of 34418 chromosomes (freq: 0.0006), European in 572 of 126678 chromosomes (freq: 0.005), Ashkenazi Jewish in 3 of 10150 chromosomes (freq: 0.0003), Finnish in 132 of 25786 chromosomes (freq: 0.005), and South Asian in 4 of 30782 chromosomes (freq: 0.0001); it was not observed in the East Asian, population. The p.Ala118= variant is not expected to have clinical significance because it does not result in a change of amino acid and is not located in a known consensus splice site. In addition, in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time although we would lean towards a more benign role for this variant. This variant is classified as likely benign. -

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jul 24, 2014
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. -

Generalized juvenile polyposis/juvenile polyposis coli Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Juvenile polyposis syndrome Benign:1
Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: 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
-0.54
CADD
Benign
7.1
DANN
Benign
0.78

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs145988618; hg19: chr18-48575160; COSMIC: COSV61687266; COSMIC: COSV61687266; API