NM_134269.3:c.322C>T

Variant names:

• chr22-31088726-C-T
• rs778759029
• NM_134269.3:c.322C>T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_134269.3(SMTN):​c.322C>T​(p.Arg108Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,160 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SMTN NM_134269.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.47

Genes affected

SMTN (HGNC:11126): (smoothelin) This gene encodes a structural protein that is found exclusively in contractile smooth muscle cells. It associates with stress fibers and constitutes part of the cytoskeleton. This gene is localized to chromosome 22q12.3, distal to the TUPLE1 locus and outside the DiGeorge syndrome deletion. Alternative splicing of this gene results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, May 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMTN	NM_134269.3	c.322C>T	p.Arg108Cys	missense_variant	Exon 5 of 21	ENST00000333137.12	NP_599031.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMTN	ENST00000333137.12	c.322C>T	p.Arg108Cys	missense_variant	Exon 5 of 21	1	NM_134269.3	ENSP00000329532.7

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461160 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 726862

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.24
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.23	.;T;.;.;.;T;T;T
Eigen	Uncertain	0.45
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.12	D
MetaRNN	Uncertain	0.53	D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.47	T
MutationAssessor	Benign	1.1	L;L;L;.;.;.;.;.
PrimateAI	Uncertain	0.76	T
PROVEAN	Benign	-1.8	N;N;N;D;.;.;D;D
REVEL	Uncertain	0.47
Sift	Pathogenic	0.0	D;D;D;D;.;.;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D;D
Polyphen		1.0	.;D;D;.;.;.;.;.
Vest4		0.91
MutPred		0.44		Loss of MoRF binding (P = 0.0126);Loss of MoRF binding (P = 0.0126);Loss of MoRF binding (P = 0.0126);Loss of MoRF binding (P = 0.0126);.;.;.;.;
MVP		0.68
MPC		0.79
ClinPred		0.91	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.31
gMVP		0.88

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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: rs778759029; hg19: chr22-31484712; COSMIC: COSV60777929; COSMIC: COSV60777929;