22-23833672-A-G

Position:

• chr22-23833672-A-G

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5_Very_Strong

The NM_003073.5(SMARCB1):​c.1087A>G​(p.Lys363Glu) variant causes a missense change involving the alteration of a 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K363N) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SMARCB1 NM_003073.5 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 9.03

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]

ACMG classification

Verdict is Pathogenic. Variant got 17 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_003073.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr22-23833674-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 561114.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=2}.
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SMARCB1. . Gene score misZ 3.6016 (greater than the threshold 3.09). Trascript score misZ 4.8554 (greater than threshold 3.09). GenCC has associacion of gene with schwannomatosis 1, familial multiple meningioma, rhabdoid tumor predisposition syndrome 1, complex neurodevelopmental disorder, intellectual disability, autosomal dominant 15, familial rhabdoid tumor, schwannomatosis, Coffin-Siris syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.887
• PP5: Variant 22-23833672-A-G is Pathogenic according to our data. Variant chr22-23833672-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 212263.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCB1	NM_003073.5	c.1087A>G	p.Lys363Glu	missense_variant	8/9	ENST00000644036.2
SMARCB1	NM_001362877.2	c.1141A>G	p.Lys381Glu	missense_variant	8/9
SMARCB1	NM_001317946.2	c.1114A>G	p.Lys372Glu	missense_variant	8/9
SMARCB1	NM_001007468.3	c.1060A>G	p.Lys354Glu	missense_variant	8/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCB1	ENST00000644036.2	c.1087A>G	p.Lys363Glu	missense_variant	8/9		NM_003073.5	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Intellectual disability, autosomal dominant 15 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	3billion	Oct 02, 2021	Same nucleotide change resulting in same amino acid change has been previously reported as pathogenic/likely pathogeic with strong evidence (ClinVar VCV000212263.2, PS1). It is not observed in the gnomAD v2.1.1 dataset (PM2). The variant was observed as assumed (i.e. paternity and maternity not confirmed) de novoo (3billion dataset, PM6). In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.874, 3Cnet: 0.943, PP3). Patient's phenotype is considered compatible with Coffin-Siris syndrome 3 (3billion dataset, PP4). Therefore, this variant is classified as likely pathogenic according to the recommendation of ACMG/AMP guideline. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	May 22, 2015	- -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics

May 09, 2017

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	.;D;T;.
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.94	D
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.89	D;D;D;D
MetaSVM	Uncertain	0.58	D
MutationAssessor	Pathogenic	3.5	.;M;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Uncertain	-3.1	D;.;D;.
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0020	D;.;D;.
Sift4G	Uncertain	0.056	T;.;T;.
Polyphen		0.88, 0.92	.;P;P;.
Vest4		0.80
MutPred		0.67		.;.;Loss of methylation at K372 (P = 0.0037);.;
MVP		0.96
MPC		2.8
ClinPred		0.99	D
GERP RS		4.8
Varity_R		0.88
gMVP		0.99

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: rs797045989; hg19: chr22-24175859;