rs1555440093

Variant names:

• chr15-66781198-G-A
• rs1555440093
• NM_005585.5:c.1154G>A

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_005585.5(SMAD6):​c.1154G>A​(p.Ser385Asn) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 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. S385R) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SMAD6 NM_005585.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.33
• Publications: 0 publications found

Genes affected

SMAD6 (HGNC:6772): (SMAD family member 6) The protein encoded by this gene belongs to the SMAD family of proteins, which are related to Drosophila 'mothers against decapentaplegic' (Mad) and C. elegans Sma. SMAD proteins are signal transducers and transcriptional modulators that mediate multiple signaling pathways. This protein functions in the negative regulation of BMP and TGF-beta/activin-signalling. Multiple transcript variants have been found for this gene.[provided by RefSeq, Sep 2014]

SMAD6 Gene-Disease associations (from GenCC):

• craniosynostosis 7

  Inheritance: AD, Unknown Classification: STRONG, MODERATE, LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia
• radioulnar synostosis, nonsyndromic, susceptibility to

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• aortic valve disease 2

  Inheritance: AD, Unknown Classification: MODERATE, LIMITED Submitted by: Ambry Genetics, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• familial bicuspid aortic valve

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• congenital radioulnar synostosis

  Inheritance: AR, Unknown Classification: SUPPORTIVE, LIMITED Submitted by: Ambry Genetics, Orphanet
• congenital heart defects, multiple types

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.40538517).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMAD6	NM_005585.5	c.1154G>A	p.Ser385Asn	missense_variant	Exon 4 of 4	ENST00000288840.10	NP_005576.3
SMAD6	XM_011521561.3	c.371G>A	p.Ser124Asn	missense_variant	Exon 4 of 4		XP_011519863.1
SMAD6	NR_027654.2	n.2309G>A		non_coding_transcript_exon_variant	Exon 5 of 5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMAD6	ENST00000288840.10	c.1154G>A	p.Ser385Asn	missense_variant	Exon 4 of 4	1	NM_005585.5	ENSP00000288840.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Aortic valve disease 2 Uncertain:1

Apr 09, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine with asparagine at codon 385 of the SMAD6 protein (p.Ser385Asn). The serine residue is highly conserved and there is a small physicochemical difference between serine and asparagine. In summary, this variant is a novel missense change that is not predicted to affect protein function. There is no indication that it causes disease, but the available evidence is currently insufficient to prove that conclusively. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The asparagine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a SMAD6-related disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Uncertain	0.029	T
BayesDel_noAF	Benign	-0.20
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.82	D
Eigen	Benign	0.058
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Uncertain	0.91	D
LIST_S2	Benign	0.81	T
M_CAP	Benign	0.053	D
MetaRNN	Benign	0.41	T
MetaSVM	Uncertain	0.53	D
MutationAssessor	Benign	1.4	L
PhyloP100		6.3
PrimateAI	Uncertain	0.76	T
PROVEAN	Benign	-1.6	N
REVEL	Uncertain	0.42
Sift	Benign	0.045	D
Sift4G	Benign	0.15	T
Polyphen		0.097	B
Vest4		0.11
MutPred		0.42		Loss of phosphorylation at S385 (P = 0.0337);
MVP		0.86
MPC		0.29
ClinPred		0.95	D
GERP RS		4.7
Varity_R		0.49
gMVP		0.23
Mutation Taster		=72/28	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

Other links and lift over

dbSNP: rs1555440093; hg19: chr15-67073536;