rs1555777820

Positions:

• chr19-11019685-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_001387283.1(SMARCA4):​c.2600A>G​(p.Lys867Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. K867K) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.22

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 Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_001387283.1
• 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, 0.89

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.2600A>G	p.Lys867Arg	missense_variant	18/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.2600A>G	p.Lys867Arg	missense_variant	18/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.2600A>G	p.Lys867Arg	missense_variant	18/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.2600A>G	p.Lys867Arg	missense_variant	18/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Rhabdoid tumor predisposition syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 11, 2021

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This variant has not been reported in the literature in individuals affected with SMARCA4-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 867 of the SMARCA4 protein (p.Lys867Arg). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.46
BayesDel_addAF	Uncertain	0.16	D
BayesDel_noAF	Uncertain	-0.010
CADD	Uncertain	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.88	D;.;D;.;.;.;.;.;.;.;D;.;.;.;.;.;T;D;.;.;.;.
Eigen	Uncertain	0.39
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Pathogenic	1.0	D
M_CAP	Pathogenic	0.42	D
MetaRNN	Pathogenic	0.89	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.60	D
MutationAssessor	Benign	0.070	N;.;.;.;N;N;.;N;N;N;N;N;N;N;N;N;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.79	T
PROVEAN	Uncertain	-2.6	D;.;.;.;.;.;.;.;.;.;D;.;D;.;D;.;.;D;.;.;.;.
REVEL	Pathogenic	0.75
Sift	Benign	0.42	T;.;.;.;.;.;.;.;.;.;T;.;T;.;T;.;.;T;.;.;.;.
Sift4G	Benign	0.45	T;.;.;.;.;.;.;.;.;.;T;.;T;T;T;T;T;T;.;.;.;.
Polyphen		0.99	D;.;D;.;.;.;.;.;.;.;D;.;.;.;.;.;.;D;.;.;.;.
Vest4		0.38
MutPred		0.76		Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);Gain of MoRF binding (P = 0.0797);.;Gain of MoRF binding (P = 0.0797);.;.;.;.;
MVP		0.92
MPC		2.9
ClinPred		0.96	D
GERP RS		4.1
Varity_R		0.44
gMVP		0.85

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: rs1555777820; hg19: chr19-11130361;