chr19-10985349-CAG-C

Variant names:

• chr19-10985349-CAG-C
• rs780424104
• NM_001387283.1:c.300_301delAG

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001387283.1(SMARCA4):​c.300_301delAG​(p.Gly102ProfsTer26) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,736 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 8.67
• Publications: 1 publications found

Genes affected

SMARCA4 (HGNC:11100): (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4) The protein encoded by this gene is a member of the SWI/SNF family of proteins and is similar to the brahma protein of Drosophila. Members of this family have helicase and ATPase activities and are thought to regulate transcription of certain genes by altering the chromatin structure around those genes. The encoded protein is part of the large ATP-dependent chromatin remodeling complex SNF/SWI, which is required for transcriptional activation of genes normally repressed by chromatin. In addition, this protein can bind BRCA1, as well as regulate the expression of the tumorigenic protein CD44. Mutations in this gene cause rhabdoid tumor predisposition syndrome type 2. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2012]

SMARCA4 Gene-Disease associations (from GenCC):

• Coffin-Siris syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet, Illumina
• intellectual disability, autosomal dominant 16

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• rhabdoid tumor predisposition syndrome 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, ClinGen, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• uterine corpus sarcoma

  Inheritance: AR Classification: MODERATE Submitted by: Genomics England PanelApp
• familial rhabdoid tumor

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary nonpolyposis colon cancer

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 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 19-10985349-CAG-C is Pathogenic according to our data. Variant chr19-10985349-CAG-C is described in ClinVar as [Pathogenic]. Clinvar id is 470331.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMARCA4	NM_001387283.1	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 36	ENST00000646693.2	NP_001374212.1
SMARCA4	NM_003072.5	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 35	ENST00000344626.10	NP_003063.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMARCA4	ENST00000646693.2	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 36		NM_001387283.1	ENSP00000495368.1
SMARCA4	ENST00000344626.10	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 35	1	NM_003072.5	ENSP00000343896.4
SMARCA4	ENST00000643549.1	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 35			ENSP00000493975.1
SMARCA4	ENST00000541122.6	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 4 of 35	5		ENSP00000445036.2
SMARCA4	ENST00000643296.1	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 34			ENSP00000496635.1
SMARCA4	ENST00000644737.1	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 3 of 34			ENSP00000495548.1
SMARCA4	ENST00000589677.5	c.300_301delAG	p.Gly102ProfsTer26	frameshift_variant	Exon 4 of 35	5		ENSP00000464778.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461736 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 727180

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86242

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53320

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111972

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Rhabdoid tumor predisposition syndrome 2 Pathogenic:1

Sep 20, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This premature translational stop signal has been observed in individual(s) with small cell carcinoma of the ovary, hypercalcemic type (PMID: 26230154). This sequence change creates a premature translational stop signal (p.Gly102Profs*26) in the SMARCA4 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SMARCA4 are known to be pathogenic (PMID: 24658001, 24658002). This variant is not present in population databases (gnomAD no frequency). This variant is also known as c.301delAG. ClinVar contains an entry for this variant (Variation ID: 470331). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		8.7
Mutation Taster		=0/200	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs780424104; hg19: chr19-11096025;