SMARCB1

protein-coding

SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily b, member 1, the group of Protein phosphatase 1 regulatory subunits|BAF complex|PBAF complex

Gene summary

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]

Previous symbols:
  • SNF5L1

MANE transcript

NM_003073.5

Inheritance

AD

ClinVar variants

P:130U:526B:354

Top phenotype

Schwannomatosis 1; Rhabdoid tumor predisposition syndrome 1

gnomAD constraint

pLI —, LoF o/e 0.05

Max pathogenic AF

—

Genomic locus

chr22:23,786,931-23,838,009

External References & Databases

Transcript & Mutation Effects

hg38 • Region Span ~51.1 kb
Loading mutation effect viewer...

GenCC Phenotypes & Disease Associations

Curated gene-disease validity assertions and inheritance patterns

familial multiple meningiomaSUPPORTIVE

Inheritance Pattern: AD

Disease ID:MONDO:0016995

Submitter: Orphanet

SMARCB1-related schwannomatosisDEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0024517

Submitter: G2P

Coffin-Siris syndromeDEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0015452

Submitter: ClinGen

*SMARCB1* was first reported in relation to autosomal dominant Coffin-Siris syndrome (CSS) in 2012 (PMID: 22426308). Coffin-Siris syndrome is characterized by intellectual disability, coarse facial features, hypertrichosis, sparse scalp hair, and hypoplastic or absent fifth fingernails or toenails. Five missense variants and inframe deletions, including recurrent p.(Lys364del) and p.(Arg37His), reported in 20 probands in 6 publications (PMIDs: 22426308, 23815551, 23906836, 23929686, 25168959, 29907796) are included in this curation. More evidence is available in the literature, but the maximum score for genetic evidence (12 points) has been reached. The mechanism for disease is dominant-negative (PMID: 31759698). This gene-disease relationship is also supported by animal and cell culture models (PMIDs: 31273213, 31759698). Mice with heterozygous disruption of *Smarcb1* exhibit brain midline abnormalities like those seen in CSS individuals (PMID: 31273213). In human induced pluripotent stem cells genetically modified to harbor the recurrent inframe variant p.(Lys364del), neuron count and neurite outgrwoth are diminished, and gene expression is downregulated (PMID: 31759698). In summary, there is definitive evidence to support the relationship between *SMARCB1* and autosomal dominant Coffin-Siris syndrome. This has been repeatedly demonstrated in both the research and clinical diagnostic settings and has been upheld over time. This classification was approved by the ClinGen Intellectual Disability and Autism Gene Curation Expert Panel on August 15, 2023 (SOP Version 9).

rhabdoid tumor predisposition syndrome 1STRONG

Inheritance Pattern: AD

Disease ID:MONDO:0012252

Submitter: Genomics England PanelApp

intellectual disability, autosomal dominant 15STRONG

Inheritance Pattern: AD

Disease ID:MONDO:0013820

Submitter: PanelApp Australia

rhabdoid tumor predisposition syndrome 1DEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0012252

Submitter: ClinGen

There is abundant published evidence associating the SMARCB1 gene with rhabdoid tumor predisposition syndrome 1 (RTPS) since the gene-disease relationship was first proposed by Sevenet et al. (1999). Multiple case level studies have been performed with RTPS patients that have variants in the SMARCB1 gene. SMARCA4, another subunit of the SWI/SNF chromatin remodeling complexes, also cause RTPS. SMARCB1 was absent from neoplastic cells of all tested AT/RTs of RTPS patients in immunohistochemical analysis. Multiple Smarcb1 haploinsufficiency mice models indicate the development of malignant rhabdoid tumors in mice. All of these types of evidence are consistent with a definitive relationship between the SMARCB1 gene and rhabdoid tumor predisposition syndrome 1 (RTPS).

complex neurodevelopmental disorderLIMITED

Inheritance Pattern: AD

Disease ID:MONDO:0100038

Submitter: Ambry Genetics

SMARCB1-related schwannomatosisSTRONG

Inheritance Pattern: AD

Disease ID:MONDO:0024517

Submitter: Ambry Genetics

intellectual disability, autosomal dominant 15DEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0013820

Submitter: G2P

schwannomatosisSUPPORTIVE

Inheritance Pattern: AD

Disease ID:MONDO:0008075

Submitter: Orphanet

familial rhabdoid tumorSUPPORTIVE

Inheritance Pattern: AD

Disease ID:MONDO:0016473

Submitter: Orphanet

Coffin-Siris syndromeSUPPORTIVE

Inheritance Pattern: AD

Disease ID:MONDO:0015452

Submitter: Orphanet

rhabdoid tumor predisposition syndrome 1DEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0012252

Submitter: Ambry Genetics

rhabdoid tumor predisposition syndrome 1STRONG

Inheritance Pattern: AD

Disease ID:MONDO:0012252

Submitter: Labcorp Genetics (formerly Invitae)

intellectual disability, autosomal dominant 15STRONG

Inheritance Pattern: AD

Disease ID:MONDO:0013820

Submitter: Labcorp Genetics (formerly Invitae)

rhabdoid tumor predisposition syndrome 1DEFINITIVE

Inheritance Pattern: AD

Disease ID:MONDO:0012252

Submitter: G2P

intellectual disability, autosomal dominant 15MODERATE

Inheritance Pattern: AD

Disease ID:MONDO:0013820

Submitter: Ambry Genetics

Clinical Genomic Database (CGD)

Schwannomatosis 1; Rhabdoid tumor predisposition syndrome 1AD

Manifestation: Cardiovascular; Dermatologic; Musculoskeletal; Neurologic; Oncologic; Genitourinary

Intervention: Oncologic

Rationale: Surveillance/early treatment of tumors may reduce morbidity

Refs: 6091860; 2543225; 9737241; 10521299; 17357086; 18285426; 18072270; 19582488; 20930055; 22426308; 22038540Source: CGD (NHGRI)

ClinVar Associated Diseases & Phenotypes

Reported disease conditions connected to SMARCB1 variants in ClinVar

27 Conditions Cataloged
not providedTotal: 929
Hereditary cancer-predisposing syndromeTotal: 735
Rhabdoid tumor predisposition syndrome 1Total: 67
not specifiedTotal: 59
Intellectual disability, autosomal dominant 15Total: 47
SMARCB1-related disorderTotal: 41
SMARCB1-related schwannomatosisTotal: 33
Coffin-Siris syndromeTotal: 9

ClinVar Variants & Pathogenicity by Type

Statistics based on transcript NM_003073.5. Only rare variants are included.

We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.

Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.

EffectPLPVUSLBBSum
synonymous
6
clinvar
336
clinvar
1
clinvar
343
missense
3
clinvar
29
clinvar
501
clinvar
16
clinvar
549
nonsense
20
clinvar
4
clinvar
2
clinvar
26
start loss
4
clinvar
1
clinvar
5
frameshift
38
clinvar
11
clinvar
7
clinvar
56
splice donor/acceptor (+/-2bp)
7
clinvar
18
clinvar
6
clinvar
31
Total686252635311010

Highest pathogenic variant AF is 0.0000082112365

Loading ClinVar variants...

Transcript Catalog

Annotated transcript isoforms across RefSeq and Ensembl databases

Showing 4 of 53 transcripts
Transcript IDSourceProtein IDCoding ExonsMANE Status
NM_003073.5RefSeqNP_003064.29MANE Select
ENST00000644036.2EnsemblENSP00000494049.29MANE Select
NM_001007468.3RefSeqNP_001007469.19Standard
NM_001317946.2RefSeqNP_001304875.19Standard

Gene Ontology (GO) Annotations & Pathways

Biological processes, molecular functions, cellular components and pathways

Pathways ConsensusPathDB

  • Thermogenesis - Homo sapiens (human)
  • Hepatocellular carcinoma - Homo sapiens (human)
  • Tumor suppressor activity of SMARCB1
  • Gene expression (Transcription)
  • RUNX1 interacts with co-factors whose precise effect on RUNX1 targets is not known

Biological Process

  • RNA polymerase I preinitiation complex assembly
  • nucleosome disassembly
  • chromatin remodeling
  • regulation of transcription by RNA polymerase II
  • cell cycle

Molecular Function

  • RNA polymerase II proximal promoter sequence-specific DNA binding
  • RNA polymerase II distal enhancer sequence-specific DNA binding
  • RNA polymerase I CORE element sequence-specific DNA binding
  • p53 binding
  • DNA binding

Cellular Component

  • nuclear chromatin
  • fibrillar center
  • nucleus
  • nucleoplasm
  • nucleolus

gnomAD Constraint

Source: gnomAD

Gene type
protein_coding
Transcript type
protein_coding
Transcript
ENST00000263121
Coding exons
9
Length
47554
Individuals with no LoFs
125742
Homozygous LoFs
0
Heterozygous LoFs
3
Defined
125745
p
0.0000119
Z-ScoreObservedExpectedObserved/ExpectedMutation RateTotal Possible
Missense3.60742270.3270.00001452537
Missense (PolyPhen)2067.5780.29595718
Synonymous-0.3469994.71.050.00000691729
Loss of Function4.10121.60.04640.00000131234

Population LoF Frequency

PopulationCAFp-valueStatus
African00.0absent
Latino/Admixed American0.0000290.000029rare
Ashkenazi Jewish0.0000990.000099rare
East Asian00.0absent
Finnish00.0absent
European (Non-Finnish)0.00000880.0000088rare
South Asian00.0absent
Other00.0absent

dbNSFP Gene Annotations

Source: dbNSFP

Function
FUNCTION: Core component of the BAF (hSWI/SNF) complex. This ATP- dependent chromatin-remodeling complex plays important roles in cell proliferation and differentiation, in cellular antiviral activities and inhibition of tumor formation. The BAF complex is able to create a stable, altered form of chromatin that constrains fewer negative supercoils than normal. This change in supercoiling would be due to the conversion of up to one-half of the nucleosomes on polynucleosomal arrays into asymmetric structures, termed altosomes, each composed of 2 histones octamers. Stimulates in vitro the remodeling activity of SMARCA4/BRG1/BAF190A. Involved in activation of CSF1 promoter. Belongs to the neural progenitors- specific chromatin remodeling complex (npBAF complex) and the neuron-specific chromatin remodeling complex (nBAF complex). During neural development a switch from a stem/progenitor to a postmitotic chromatin remodeling mechanism occurs as neurons exit the cell cycle and become committed to their adult state. The transition from proliferating neural stem/progenitor cells to postmitotic neurons requires a switch in subunit composition of the npBAF and nBAF complexes. As neural progenitors exit mitosis and differentiate into neurons, npBAF complexes which contain ACTL6A/BAF53A and PHF10/BAF45A, are exchanged for homologous alternative ACTL6B/BAF53B and DPF1/BAF45B or DPF3/BAF45C subunits in neuron-specific complexes (nBAF). The npBAF complex is essential for the self-renewal/proliferative capacity of the multipotent neural stem cells. The nBAF complex along with CREST plays a role regulating the activity of genes essential for dendrite growth (By similarity). Plays a key role in cell-cycle control and causes cell cycle arrest in G0/G1. {ECO:0000250|UniProtKB:Q9Z0H3, ECO:0000269|PubMed:10078207, ECO:0000269|PubMed:12226744, ECO:0000269|PubMed:14604992, ECO:0000269|PubMed:16267391, ECO:0000269|PubMed:16314535, ECO:0000269|PubMed:9448295}.;
Disease
DISEASE: Rhabdoid tumor predisposition syndrome 1 (RTPS1) [MIM:609322]: A familial cancer syndrome predisposing to renal or extrarenal malignant rhabdoid tumors and to a variety of tumors of the central nervous system, including choroid plexus carcinoma, medulloblastoma, and central primitive neuroectodermal tumors. Rhabdoid tumors are the most aggressive and lethal malignancies occurring in early childhood. {ECO:0000269|PubMed:9671307, ECO:0000269|PubMed:9892189}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Schwannomatosis 1 (SWNTS1) [MIM:162091]: A cancer syndrome in which patients develop multiple non-vestibular schwannomas, benign neoplasms that arise from Schwann cells of the cranial, peripheral, and autonomic nerves. {ECO:0000269|PubMed:17357086, ECO:0000269|PubMed:18072270}. Note=Disease susceptibility is associated with variations affecting the gene represented in this entry.; DISEASE: Coffin-Siris syndrome 3 (CSS3) [MIM:614608]: A form of Coffin-Siris syndrome, a congenital multiple malformation syndrome with broad phenotypic and genetic variability. Cardinal features are intellectual disability, coarse facial features, hypertrichosis, and hypoplastic or absent fifth digit nails or phalanges. Additional features include malformations of the cardiac, gastrointestinal, genitourinary, and/or central nervous systems. Sucking/feeding difficulties, poor growth, ophthalmologic abnormalities, hearing impairment, and spinal anomalies are common findings. Both autosomal dominant and autosomal recessive inheritance patterns have been reported. {ECO:0000269|PubMed:22426308, ECO:0000269|PubMed:22726846, ECO:0000269|PubMed:23906836}. Note=The disease is caused by mutations affecting the gene represented in this entry.;

Recessive Scores

pRec
0.298

Intolerance Scores

RVIS EVS
-0.34
RVIS percentile EVS
30.07

Essentials

Essential (CRISPR)
E
Essential (CRISPR2)
E
Essential (gene trap)
E
Indispensability pred.
E
Indispensability score
1.00

Gene Damage Prediction

AllRecessiveDominant
MendelianLowLowLow
Primary ImmunodeficiencyMediumLowMedium
CancerLowLowLow
For research and educational, non-commercial use only. Not for clinical or diagnostic use. GeneBe does not provide medical advice. Data use for AI modeling is prohibited: if used, the cost is $0.001 per byte of downloaded uncompressed data.