19-10984195-G-C

Position:

• chr19-10984195-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001387283.1(SMARCA4):​c.44G>C​(p.Gly15Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,150 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G15D) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.75

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• 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=0.41201955).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.44G>C	p.Gly15Ala	missense_variant	2/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.44G>C	p.Gly15Ala	missense_variant	2/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.44G>C	p.Gly15Ala	missense_variant	2/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.44G>C	p.Gly15Ala	missense_variant	2/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461150 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726906

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Rhabdoid tumor predisposition syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 11, 2023

ClinVar contains an entry for this variant (Variation ID: 824949). This variant has not been reported in the literature in individuals affected with SMARCA4-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 15 of the SMARCA4 protein (p.Gly15Ala). 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 not expected to disrupt SMARCA4 protein function. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 28, 2023

The p.G15A variant (also known as c.44G>C), located in coding exon 1 of the SMARCA4 gene, results from a G to C substitution at nucleotide position 44. The glycine at codon 15 is replaced by alanine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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	0.22
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.52	D;.;T;.;.;.;.;.;.;.;D;.;.;.;.;.;.;T;T
Eigen	Benign	0.14
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.83	.;T;.;.;.;.;T;.;.;.;T;D;.;T;T;T;T;D;D
M_CAP	Uncertain	0.10	D
MetaRNN	Benign	0.41	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.058	T
MutationAssessor	Benign	1.1	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	0.82	D
PROVEAN	Benign	-2.2	N;.;.;.;.;.;.;.;.;.;N;.;.;N;.;N;.;N;N
REVEL	Uncertain	0.38
Sift	Benign	0.054	T;.;.;.;.;.;.;.;.;.;T;.;.;T;.;T;.;T;T
Sift4G	Benign	0.46	T;.;.;.;.;.;.;.;.;.;T;.;.;T;T;T;T;T;T
Polyphen		0.32	B;.;B;.;.;.;.;.;.;.;B;.;.;.;.;.;.;.;B
Vest4		0.42
MutPred		0.20		Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);Loss of catalytic residue at G15 (P = 0.0673);
MVP		0.80
MPC		0.28
ClinPred		0.89	D
GERP RS		5.0
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		3.7
Varity_R		0.14
gMVP		0.47

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: rs1060502077; hg19: chr19-11094871;