rs730881955

Variant names:

• chr18-51078442-T-A
• rs730881955
• NM_005359.6:c.1634T>A

Your query was ambiguous. Multiple possible variants found:

• chr18-51078442-T-A
• chr18-51078442-T-C
• chr18-51078442-T-G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM1 BS2

The NM_005359.6(SMAD4):​c.1634T>A​(p.Ile545Asn) variant causes a missense change. The variant allele was found at a frequency of 0.0000041 in 1,461,788 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I545T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: SMAD4 NM_005359.6 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 6.15
• Publications: 1 publications found

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: ClinGen, PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
• Myhre syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Orphanet
• generalized juvenile polyposis/juvenile polyposis coli

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• 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

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM1: In a domain MH2 (size 229) in uniprot entity SMAD4_HUMAN there are 35 pathogenic changes around while only 2 benign (95%) in NM_005359.6
• BS2: High AC in GnomAdExome4 at 6 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005359.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD4	NM_005359.6	MANE Select	c.1634T>A	p.Ile545Asn	missense	Exon 12 of 12	NP_005350.1	Q13485
	SMAD4	NM_001407041.1		c.1634T>A	p.Ile545Asn	missense	Exon 12 of 12	NP_001393970.1	A0A024R274
	SMAD4	NM_001407042.1		c.1634T>A	p.Ile545Asn	missense	Exon 12 of 12	NP_001393971.1	Q13485

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMAD4	ENST00000342988.8	TSL:5 MANE Select	c.1634T>A	p.Ile545Asn	missense	Exon 12 of 12	ENSP00000341551.3	Q13485
	SMAD4	ENST00000591126.5	TSL:1	n.3635T>A		non_coding_transcript_exon	Exon 8 of 8
	SMAD4	ENST00000714264.1		c.1715T>A	p.Ile572Asn	missense	Exon 12 of 12	ENSP00000519545.1	A0AAQ5BHY6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000410 AC: 6 AN: 1461788 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727208

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1111934

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Hereditary cancer-predisposing syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection (1)
-	1	-	Juvenile polyposis syndrome (1)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	28
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.87	D
Eigen	Uncertain	0.65
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.45	D
MetaRNN	Uncertain	0.69	D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Uncertain	2.7	M
PhyloP100		6.2
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-3.1	D
REVEL	Pathogenic	0.74
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		0.93	P
Vest4		0.55
MutPred		0.30		Gain of disorder (P = 0.0166)
MVP		0.93
MPC		2.7
ClinPred		0.93	D
GERP RS		6.0
Varity_R		0.80
gMVP		0.89
Mutation Taster		=8/92	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

Other links and lift over

dbSNP: rs730881955; hg19: chr18-48604812;