rs145805120

chr18-51054908-A-G

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_005359.6(SMAD4):c.582A>G(p.Thr194=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000328 in 1,614,180 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 (★★).

• Frequency:
  • Genomes: 𝑓 0.00016 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000020 (0 hom.)
• Consequence: SMAD4 NM_005359.6 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:9
• Conservation: PhyloP100: -1.19

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]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.65).
• BP6: Variant 18-51054908-A-G is Benign according to our data. Variant chr18-51054908-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 380411.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-1.19 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000158 (24/152352) while in subpopulation AFR AF= 0.000481 (20/41578). AF 95% confidence interval is 0.000319. There are 0 homozygotes in gnomad4. There are 14 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High AC in GnomAd at 24 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMAD4	NM_005359.6	c.582A>G	p.Thr194=	synonymous_variant	5/12	ENST00000342988.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMAD4	ENST00000342988.8	c.582A>G	p.Thr194=	synonymous_variant	5/12	5	NM_005359.6	P1

Frequencies

GnomAD3 genomes AF: 0.000158 AC: 24 AN: 152234 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000482

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000262

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

GnomAD3 exomes AF: 0.0000756 AC: 19 AN: 251484 Hom.: 0 AF XY: 0.0000515 AC XY: 7 AN XY: 135918

Gnomad AFR exome AF: 0.000984

Gnomad AMR exome AF: 0.0000867

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000198 AC: 29 AN: 1461828 Hom.: 0 Cov.: 31 AF XY: 0.0000138 AC XY: 10 AN XY: 727224

Gnomad4 AFR exome AF: 0.000597

Gnomad4 AMR exome AF: 0.000112

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: 8.99e-7

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome AF: 0.000158 AC: 24 AN: 152352 Hom.: 0 Cov.: 32 AF XY: 0.000188 AC XY: 14 AN XY: 74502

Gnomad4 AFR AF: 0.000481

Gnomad4 AMR AF: 0.000261

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000693 Hom.: 0

Bravo AF: 0.000196

Asia WGS AF: 0.000289 AC: 1 AN: 3478

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:9

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:3

Likely benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	May 25, 2017	- -
Likely benign, criteria provided, single submitter	clinical testing	GeneDx	May 27, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	May 03, 2016	Variant summary: The SMAD4 c.582A>G variant affects a non-conserved nucleotide, resulting in a synonymous change. Mutation Taster predicts a damaging outcome for this variant. This variant was found in 13/121412 control chromosomes at a frequency of 0.0001071, which is about 54 times the maximal expected frequency of a pathogenic SMAD4 allele (0.000002), suggesting this variant is benign. In addition, one clinical laboratory classified this variant as benign, and the variant was found to co-occur with a pathogenic PMS2 variant (c.2186_2187delTC) in one internal specimen. The variant of interest has not, to our knowledge, been reported in affected individuals via publications and/or reputable databases/clinical laboratories; nor evaluated for functional impact by in vivo/vitro studies. Taken together, this variant was classified as benign. -

Hereditary cancer-predisposing syndrome Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 02, 2016	- -
Benign, criteria provided, single submitter	curation	Sema4, Sema4	Apr 23, 2021	- -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Quest Diagnostics Nichols Institute San Juan Capistrano

May 23, 2017

- -

Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 07, 2015

This alteration is classified as likely benign based on a combination of the following: 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. -

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jan 11, 2024

- -

Juvenile polyposis syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jan 12, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.65
Cadd	Benign	4.7
Dann	Benign	0.65
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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

Other links and lift over

dbSNP: rs145805120; hg19: chr18-48581278;