chr18-51054996-G-A

Position:

chr18-51054996-G-A

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_005359.6(SMAD4):c.667+3G>A variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000349 in 1,606,290 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

SMAD4
NM_005359.6 splice_donor_region, intron

Scores

Splicing: ADA: 0.0003288

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:7

Conservation

PhyloP100: 2.15

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.36).

BP6

Variant 18-51054996-G-A is Benign according to our data. Variant chr18-51054996-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 327111.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=7, Uncertain_significance=3}.

BS2

High AC in GnomAdExome4 at 53 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SMAD4	NM_005359.6 linkuse as main transcript	c.667+3G>A		splice_donor_region_variant, intron_variant		ENST00000342988.8	NP_005350.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SMAD4	ENST00000342988.8 linkuse as main transcript	c.667+3G>A		splice_donor_region_variant, intron_variant		5	NM_005359.6	ENSP00000341551	P1

Frequencies

GnomAD3 genomes

AF:

0.0000198

AC:

AN:

151806

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000295

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

250770

Hom.:

AF XY:

0.0000148

AC XY:

AN XY:

135556

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000364

AC:

AN:

1454484

Hom.:

Cov.:

AF XY:

0.0000332

AC XY:

AN XY:

723978

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000443

Gnomad4 OTH exome

AF:

0.0000665

GnomAD4 genome

AF:

0.0000198

AC:

AN:

151806

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74158

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000295

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000151

EpiCase

AF:

0.0000546

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:7

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome

Uncertain:1Benign:2

Likely benign, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Nov 30, 2023	- -
Likely benign, criteria provided, single submitter	clinical testing	Myriad Genetics, Inc.	Dec 19, 2023	This variant is considered likely benign. This variant is intronic and is not expected to impact mRNA splicing. -
Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

not provided

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	May 18, 2020	This variant is associated with the following publications: (PMID: 26976419) -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Sep 01, 2023	SMAD4: BP4 -

Myhre syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Generalized juvenile polyposis/juvenile polyposis coli

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 15, 2020

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. -

Hereditary cancer-predisposing syndrome

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jan 19, 2023

- -

Juvenile polyposis syndrome

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 13, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.36

CADD

Benign

DANN

Benign

0.80

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.00033

dbscSNV1_RF

Benign

0.0

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over