chr22-23791865-ATGGTAAAAAAACA-TACC

Position:

• chr22-23791865-ATGGTAAAAAAACA-TACC

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP3 PP5

The ENST00000407422.8(SMARCB1):​c.203_205+11delinsTACC variant causes a splice donor, splice donor 5th base, coding sequence, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars). Synonymous variant affecting the same amino acid position (i.e. H68H) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: SMARCB1 ENST00000407422.8 splice_donor, splice_donor_5th_base, coding_sequence, intron
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.70

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 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.2, offset of 17, new splice context is: aggGTgcgt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP
• PP5: Variant 22-23791865-ATGGTAAAAAAACA-TACC is Pathogenic according to our data. Variant chr22-23791865-ATGGTAAAAAAACA-TACC is described in ClinVar as [Pathogenic]. Clinvar id is 8028.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCB1	NM_003073.5	c.203_216delinsTACC	p.His68LeufsTer14	frameshift_variant	2/9	ENST00000644036.2
SMARCB1	NM_001362877.2	c.203_216delinsTACC	p.His68LeufsTer14	frameshift_variant	2/9
SMARCB1	NM_001007468.3	c.203_205+11delinsTACC		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	2/9
SMARCB1	NM_001317946.2	c.203_205+11delinsTACC		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	2/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCB1	ENST00000644036.2	c.203_216delinsTACC	p.His68LeufsTer14	frameshift_variant	2/9		NM_003073.5	A1

Frequencies

GnomAD3 genomes Cov.: 33

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Schwannomatosis 1 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Feb 01, 2008

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs587776679; hg19: chr22-24134052;