22-23833613-C-T

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The NM_003073.5(SMARCB1):c.1028C>T(p.Thr343Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000929 in 1,614,100 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

SMARCB1
NM_003073.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 7.66

Variant links:

Genes affected

SMARCB1 (HGNC:11103): (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily b, member 1) The protein encoded by this gene is part of a complex that relieves repressive chromatin structures, allowing the transcriptional machinery to access its targets more effectively. The encoded nuclear protein may also bind to and enhance the DNA joining activity of HIV-1 integrase. This gene has been found to be a tumor suppressor, and mutations in it have been associated with malignant rhabdoid tumors. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Dec 2015]

SMARCB1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2

High AC in GnomAdExome4 at 14 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMARCB1	NM_003073.5 link	c.1028C>T	p.Thr343Met	missense_variant	Exon 8 of 9	ENST00000644036.2	NP_003064.2	Q12824-1
SMARCB1	NM_001362877.2 link	c.1082C>T	p.Thr361Met	missense_variant	Exon 8 of 9		NP_001349806.1
SMARCB1	NM_001317946.2 link	c.1055C>T	p.Thr352Met	missense_variant	Exon 8 of 9		NP_001304875.1	G5E975Q9H836
SMARCB1	NM_001007468.3 link	c.1001C>T	p.Thr334Met	missense_variant	Exon 8 of 9		NP_001007469.1	Q12824-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMARCB1	ENST00000644036.2 link	c.1028C>T	p.Thr343Met	missense_variant	Exon 8 of 9		NM_003073.5	ENSP00000494049.2		Q12824-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152226

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251476

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135922

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000924

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461874

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

727240

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

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:

0.000150

Gnomad4 NFE exome

AF:

0.00000360

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152226

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74370

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.00000378

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Mar 08, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Jan 29, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 343 of the SMARCB1 protein (p.Thr343Met). This variant is present in population databases (rs773457718, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with SMARCB1-related conditions. ClinVar contains an entry for this variant (Variation ID: 464320). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt SMARCB1 protein function with a negative predictive value of 80%. 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. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Nov 18, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.T343M variant (also known as c.1028C>T), located in coding exon 8 of the SMARCB1 gene, results from a C to T substitution at nucleotide position 1028. The threonine at codon 343 is replaced by methionine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Missense and in-frame variants in SMARCB1 are known to cause neurodevelopmental disorders; however, such associations with rhabdoid tumor predisposition syndrome are exceedingly rare (Kosho T et al. Am J Med Genet C Semin Med Genet. 2014 Sep;166C(3):262-75; Eaton KW et al. Pediatr Blood Cancer. 2011 Jan;56(1):7-15). Based on the supporting evidence, the association of this alteration with Coffin-Siris syndrome is unknown; however, the association of this alteration with rhabdoid tumor predisposition syndrome is unlikely. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

-0.023

BayesDel_noAF

Benign

-0.10

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.39

.;T;T;.

Eigen

Uncertain

0.49

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Uncertain

0.94

M_CAP

Uncertain

0.11

MetaRNN

Uncertain

0.57

D;D;D;D

MetaSVM

Uncertain

-0.20

MutationAssessor

Benign

1.5

.;L;.;.

PrimateAI

Pathogenic

0.92

PROVEAN

Benign

-1.5

N;.;N;.

REVEL

Uncertain

0.38

Sift

Benign

0.22

T;.;T;.

Sift4G

Benign

0.069

T;.;T;.

Polyphen

0.78, 0.88

.;P;P;.

Vest4

0.61

MutPred

0.32

.;.;Loss of phosphorylation at T352 (P = 0.0283);.;

MVP

0.60

MPC

2.0

ClinPred

0.92

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.32

gMVP

0.87

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over