19-10996507-C-T

Position:

• chr19-10996507-C-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 1P and 7B. PP2 BP4_Moderate BS1_Supporting BS2

The NM_003072.5(SMARCA4):​c.1775C>T​(p.Ala592Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,868 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: SMARCA4 NM_003072.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 2.31

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 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SMARCA4. . Gene score misZ 6.8459 (greater than the threshold 3.09). Trascript score misZ 8.7957 (greater than threshold 3.09). GenCC has associacion of gene with uterine corpus sarcoma, Coffin-Siris syndrome 1, intellectual disability, autosomal dominant 16, rhabdoid tumor predisposition syndrome 2, familial rhabdoid tumor, hereditary nonpolyposis colon cancer, Coffin-Siris syndrome.
• BP4: Computational evidence support a benign effect (MetaRNN=0.103897095).
• BS1: Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.00000479 (7/1461868) while in subpopulation MID AF= 0.000693 (4/5768). AF 95% confidence interval is 0.000236. There are 0 homozygotes in gnomad4_exome. There are 4 alleles in male gnomad4_exome subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SMARCA4	NM_001387283.1	c.1775C>T	p.Ala592Val	missense_variant	11/36	ENST00000646693.2	NP_001374212.1
SMARCA4	NM_003072.5	c.1775C>T	p.Ala592Val	missense_variant	11/35	ENST00000344626.10	NP_003063.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SMARCA4	ENST00000646693.2	c.1775C>T	p.Ala592Val	missense_variant	11/36		NM_001387283.1	ENSP00000495368.1
SMARCA4	ENST00000344626.10	c.1775C>T	p.Ala592Val	missense_variant	11/35	1	NM_003072.5	ENSP00000343896.4
SMARCA4	ENST00000643549.1	c.1775C>T	p.Ala592Val	missense_variant	11/35			ENSP00000493975.1
SMARCA4	ENST00000541122.6	c.1775C>T	p.Ala592Val	missense_variant	12/35	5		ENSP00000445036.2
SMARCA4	ENST00000643296.1	c.1775C>T	p.Ala592Val	missense_variant	11/34			ENSP00000496635.1
SMARCA4	ENST00000644737.1	c.1775C>T	p.Ala592Val	missense_variant	11/34			ENSP00000495548.1
SMARCA4	ENST00000589677.5	c.1775C>T	p.Ala592Val	missense_variant	12/35	5		ENSP00000464778.1
SMARCA4	ENST00000643995.1	c.1187C>T	p.Ala396Val	missense_variant	8/32			ENSP00000496004.1
SMARCA4	ENST00000644963.1	c.419C>T	p.Ala140Val	missense_variant	4/28			ENSP00000495599.1
SMARCA4	ENST00000644065.1	c.500C>T	p.Ala167Val	missense_variant	4/27			ENSP00000493615.1
SMARCA4	ENST00000642350.1	c.260C>T	p.Ala87Val	missense_variant	3/27			ENSP00000495355.1
SMARCA4	ENST00000643857.1	c.128C>T	p.Ala43Val	missense_variant	2/25			ENSP00000494159.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251490 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135918

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461868 Hom.: 0 Cov.: 33 AF XY: 0.00000550 AC XY: 4 AN XY: 727238

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: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Rhabdoid tumor predisposition syndrome 2 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 06, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Dec 19, 2023	This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 592 of the SMARCA4 protein (p.Ala592Val). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with SMARCA4-related conditions. ClinVar contains an entry for this variant (Variation ID: 820051). 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 not expected to disrupt SMARCA4 protein function with a negative predictive value of 95%. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 25, 2023

The p.A592V variant (also known as c.1775C>T), located in coding exon 10 of the SMARCA4 gene, results from a C to T substitution at nucleotide position 1775. The alanine at codon 592 is replaced by valine, an amino acid with similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Missense and in-frame variants in SMARCA4 are known to cause neurodevelopmental disorders; however, such associations with rhabdoid tumor predisposition syndrome including small cell carcinoma of the ovary-hypercalcemic type (SCCOHT) are exceedingly rare (Kosho T et al. Am J Med Genet C Semin Med Genet. 2014 Sep;166C(3):262-75; Jelinic P et al. Nat Genet. 2014 May;46(5):424-6). Based on the supporting evidence, the association of this alteration with Coffin-Siris syndrome is unknown; however, the association of this alteration with rhabdoid tumor predisposition syndrome is unlikely. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.072
BayesDel_addAF	Benign	-0.080	T
BayesDel_noAF	Benign	-0.35
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.27	T;.;T;.;.;.;.;.;.;.;T;.;.;.;.;.;T;T;.;.;.
Eigen	Benign	-0.45
Eigen_PC	Benign	-0.37
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.92	.;D;.;.;.;.;D;.;.;.;D;.;D;D;D;D;D;D;D;D;D
M_CAP	Benign	0.033	D
MetaRNN	Benign	0.10	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.43	T
MutationAssessor	Benign	0.0	N;.;.;.;N;N;.;N;N;N;N;N;N;N;N;N;.;.;.;.;.
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-0.92	N;.;.;.;.;.;.;.;.;.;N;.;N;.;N;.;.;N;.;.;.
REVEL	Benign	0.15
Sift	Benign	0.15	T;.;.;.;.;.;.;.;.;.;T;.;T;.;T;.;.;T;.;.;.
Sift4G	Benign	0.62	T;.;.;.;.;.;.;.;.;.;T;.;T;T;T;T;T;T;.;.;.
Polyphen		0.0010	B;.;B;.;.;.;.;.;.;.;B;.;.;.;.;.;.;B;.;.;.
Vest4		0.28
MutPred		0.11		Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);.;Loss of helix (P = 0.028);.;.;.;
MVP		0.49
MPC		1.3
ClinPred		0.18	T
GERP RS		3.8
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		2.0
Varity_R		0.053
gMVP		0.80

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1060502064; hg19: chr19-11107183;