19-11021885-A-G

Position:

• chr19-11021885-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_001387283.1(SMARCA4):​c.2777A>G​(p.Asn926Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,460 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. N926N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:3
• Conservation: PhyloP100: 9.32

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, SMARCA4
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.935

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.2777A>G	p.Asn926Ser	missense_variant	19/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.2777A>G	p.Asn926Ser	missense_variant	19/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.2777A>G	p.Asn926Ser	missense_variant	19/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.2777A>G	p.Asn926Ser	missense_variant	19/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461460 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727038

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000377

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Intellectual disability, autosomal dominant 16 Pathogenic:1 Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Center for Molecular Medicine, Children’s Hospital of Fudan University	Apr 20, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Jul 15, 2021	- -

Rhabdoid tumor predisposition syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 12, 2023

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt SMARCA4 protein function. ClinVar contains an entry for this variant (Variation ID: 470319). This missense change has been observed in individual(s) with clinical features of SMARCA4-related conditions (PMID: 34813034). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 926 of the SMARCA4 protein (p.Asn926Ser). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 13, 2019

The p.N926S variant (also known as c.2777A>G), located in coding exon 18 of the SMARCA4 gene, results from an A to G substitution at nucleotide position 2777. The asparagine at codon 926 is replaced by serine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;.;D;.;.;.;.;.;.;.;D;.;.;.;.;.;T;D;.;.;.;.
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.88	D
MetaRNN	Pathogenic	0.93	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Benign	1.6	L;.;.;.;L;L;.;L;L;L;L;L;L;L;L;L;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-4.7	D;.;.;.;.;.;.;.;.;.;D;.;D;.;D;.;.;D;.;.;.;.
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D;.;.;.;.;.;.;.;.;.;D;.;D;.;D;.;.;D;.;.;.;.
Sift4G	Pathogenic	0.0	D;.;.;.;.;.;.;.;.;.;D;.;D;D;D;D;D;D;.;.;.;.
Polyphen		1.0	D;.;D;.;.;.;.;.;.;.;D;.;.;.;.;.;.;D;.;.;.;.
Vest4		0.82
MutPred		0.79		Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);Loss of helix (P = 0.1706);.;Loss of helix (P = 0.1706);.;.;.;.;
MVP		0.96
MPC		2.8
ClinPred		0.99	D
GERP RS		4.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.96
gMVP		0.97

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: rs1555778797; hg19: chr19-11132561;