19-10984158-A-C

Position:

• chr19-10984158-A-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.7A>C​(p.Thr3Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. T3I) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 5.32

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, SMARCA4
• BP4: Computational evidence support a benign effect (MetaRNN=0.40521663).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.7A>C	p.Thr3Pro	missense_variant	2/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.7A>C	p.Thr3Pro	missense_variant	2/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.7A>C	p.Thr3Pro	missense_variant	2/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.7A>C	p.Thr3Pro	missense_variant	2/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

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	Invitae	Jun 24, 2022	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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C35"). ClinVar contains an entry for this variant (Variation ID: 661210). 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 threonine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 3 of the SMARCA4 protein (p.Thr3Pro). -
Uncertain significance, criteria provided, single submitter	clinical testing	Baylor Genetics	Dec 06, 2023	- -

Intellectual disability, autosomal dominant 16 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Jul 15, 2021

- -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 18, 2024

The p.T3P variant (also known as c.7A>C), located in coding exon 1 of the SMARCA4 gene, results from an A to C substitution at nucleotide position 7. The threonine at codon 3 is replaced by proline, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. This variant has been detected in multiple individuals with no reported features of Coffin Siris syndrome (Ambry internal data). Based on the supporting evidence, the association of this alteration with rhabdoid tumor predisposition syndrome is unknown; however, the association of this alteration with Coffin-Siris syndrome is unlikely. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.22
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.10
CADD	Uncertain	24
DANN	Uncertain	0.98
DEOGEN2	Benign	0.40	T;.;T;.;.;.;.;.;.;.;T;.;.;.;.;.;.;T;T
Eigen	Uncertain	0.23
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Uncertain	0.92	D
M_CAP	Pathogenic	0.31	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	0.013	D
MutationAssessor	Benign	1.0	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	Uncertain	0.59	T
PROVEAN	Benign	-0.85	N;.;.;.;.;.;.;.;.;.;N;.;.;N;.;N;.;N;N
REVEL	Uncertain	0.58
Sift	Uncertain	0.0080	D;.;.;.;.;.;.;.;.;.;D;.;.;D;.;D;.;D;D
Sift4G	Benign	0.21	T;.;.;.;.;.;.;.;.;.;T;.;.;T;T;T;T;T;T
Polyphen		0.92	P;.;P;.;.;.;.;.;.;.;P;.;.;.;.;.;.;.;P
Vest4		0.40
MutPred		0.26		Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);Loss of phosphorylation at T3 (P = 0.0012);
MVP		0.92
MPC		0.33
ClinPred		0.75	D
GERP RS		3.9
Varity_R		0.23
gMVP		0.10

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: rs1599927930; hg19: chr19-11094834;