22-23803395-C-T

Position:

• chr22-23803395-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_003073.5(SMARCB1):​c.601C>T​(p.Arg201*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 34)
• Consequence: SMARCB1 NM_003073.5 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.41

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 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 22-23803395-C-T is Pathogenic according to our data. Variant chr22-23803395-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 532962.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SMARCB1	NM_003073.5	c.601C>T	p.Arg201*	stop_gained	5/9	ENST00000644036.2	NP_003064.2
SMARCB1	NM_001362877.2	c.655C>T	p.Arg219*	stop_gained	5/9		NP_001349806.1
SMARCB1	NM_001317946.2	c.628C>T	p.Arg210*	stop_gained	5/9		NP_001304875.1
SMARCB1	NM_001007468.3	c.574C>T	p.Arg192*	stop_gained	5/9		NP_001007469.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SMARCB1	ENST00000644036.2	c.601C>T	p.Arg201*	stop_gained	5/9		NM_003073.5	ENSP00000494049.2

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 20, 2021

This sequence change creates a premature translational stop signal (p.Arg201*) in the SMARCB1 gene. It is expected to result in an absent or disrupted protein product. This variant is not present in population databases (ExAC no frequency). This variant has been observed in several individuals with atypical teratoid and rhabdoid tumors (PMID: 10521299, 26998479, 21208904, 24933152, 20848638, 21108436). ClinVar contains an entry for this variant (Variation ID: 532962). Loss-of-function variants in SMARCB1 are known to be pathogenic (PMID: 10521299, 21208904). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	45
DANN	Uncertain	1.0
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Benign	0.51	D
Vest4		0.95
GERP RS		0.87
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs1555877286; hg19: chr22-24145582; COSMIC: COSV54093216; COSMIC: COSV54093216;