rs1555750794

chr19-10984257-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP2

The NM_001387283.1(SMARCA4):c.106C>T(p.Pro36Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,459,408 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. P36L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.91

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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, SMARCA4

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.106C>T	p.Pro36Ser	missense_variant	2/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.106C>T	p.Pro36Ser	missense_variant	2/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.106C>T	p.Pro36Ser	missense_variant	2/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.106C>T	p.Pro36Ser	missense_variant	2/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1459408 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 725960

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: 0.0000116

Gnomad4 FIN exome AF: 0.0000191

Gnomad4 NFE exome AF: 0.00

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

Invitae

Jul 28, 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 C65"). ClinVar contains an entry for this variant (Variation ID: 537791). 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 proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 36 of the SMARCA4 protein (p.Pro36Ser). -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2022

The p.P36S variant (also known as c.106C>T), located in coding exon 1 of the SMARCA4 gene, results from a C to T substitution at nucleotide position 106. The proline at codon 36 is replaced by serine, 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). 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	Benign	0.23
BayesDel_addAF	Pathogenic	0.20	D
BayesDel_noAF	Uncertain	0.050
Cadd	Benign	23
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.74	D;.;T;.;.;.;.;.;.;.;D;.;.;.;.;.;.;T;T
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Pathogenic	0.70	D
MetaRNN	Uncertain	0.73	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.99	D
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	0.83	D
PROVEAN	Uncertain	-3.0	D;.;.;.;.;.;.;.;.;.;D;.;.;D;.;D;.;D;D
REVEL	Uncertain	0.47
Sift	Uncertain	0.0090	D;.;.;.;.;.;.;.;.;.;D;.;.;D;.;D;.;D;D
Sift4G	Benign	0.064	T;.;.;.;.;.;.;.;.;.;T;.;.;T;T;T;T;T;T
Polyphen		0.99	D;.;D;.;.;.;.;.;.;.;D;.;.;.;.;.;.;.;D
Vest4		0.61
MutPred		0.18		Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);Gain of phosphorylation at P36 (P = 0.0023);
MVP		0.77
MPC		0.26
ClinPred		0.94	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.18
gMVP		0.21

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: rs1555750794; hg19: chr19-11094933;