rs990598927

chr15-66703452-C-G

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_005585.5(SMAD6):c.194C>G(p.Pro65Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000099 in 1,272,722 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict 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. P65L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.00012 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000096 (0 hom.)
• Consequence: SMAD6 NM_005585.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.330

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]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.21273813).
• BS2: High AC in GnomAd at 18 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMAD6	NM_005585.5	c.194C>G	p.Pro65Arg	missense_variant	1/4	ENST00000288840.10
SMAD6	NR_027654.2	n.1217C>G		non_coding_transcript_exon_variant	1/5
SMAD6	XR_931827.3	n.1217C>G		non_coding_transcript_exon_variant	1/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMAD6	ENST00000288840.10	c.194C>G	p.Pro65Arg	missense_variant	1/4	1	NM_005585.5	P1
SMAD6	ENST00000557916.5	c.194C>G	p.Pro65Arg	missense_variant, NMD_transcript_variant	1/5	1
SMAD6	ENST00000612349.1	n.376C>G		non_coding_transcript_exon_variant	1/1

Frequencies

GnomAD3 genomes AF: 0.000119 AC: 18 AN: 151660 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.000193

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: 0.00318

Gnomad NFE AF: 0.000133

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000963 AC: 108 AN: 1120954 Hom.: 0 Cov.: 32 AF XY: 0.0000860 AC XY: 46 AN XY: 534936

Gnomad4 AFR exome AF: 0.000131

Gnomad4 AMR exome AF: 0.000239

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: 0.000103

Gnomad4 OTH exome AF: 0.000112

GnomAD4 genome AF: 0.000119 AC: 18 AN: 151768 Hom.: 0 Cov.: 33 AF XY: 0.0000539 AC XY: 4 AN XY: 74172

Gnomad4 AFR AF: 0.000193

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: 0.000133

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000214 Hom.: 0

Bravo AF: 0.000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Aug 24, 2023

- -

Aortic valve disease 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 19, 2024

This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 65 of the SMAD6 protein (p.Pro65Arg). This variant is present in population databases (no rsID available, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with SMAD6-related conditions. ClinVar contains an entry for this variant (Variation ID: 405518). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.084
BayesDel_addAF	Benign	-0.092	T
BayesDel_noAF	Benign	-0.37
Cadd	Benign	17
Dann	Benign	0.89
DEOGEN2	Benign	0.28	T
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.57
FATHMM_MKL	Benign	0.12	N
LIST_S2	Benign	0.43	T
M_CAP	Pathogenic	0.67	D
MetaRNN	Benign	0.21	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.81	L
MutationTaster	Benign	0.89	D;D
PrimateAI	Pathogenic	0.94	D
PROVEAN	Benign	-0.26	N
REVEL	Benign	0.098
Sift	Benign	0.25	T
Sift4G	Benign	0.35	T
Polyphen		0.43	B
Vest4		0.14
MutPred		0.25		Loss of loop (P = 0.0128);
MVP		0.75
MPC		1.2
ClinPred		0.12	T
GERP RS		1.6
Varity_R		0.063
gMVP		0.29

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

Other links and lift over

dbSNP: rs990598927; hg19: chr15-66995790;