rs1225673675

Positions:

• chr19-10985276-A-G
• chr19-10985276-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 3P and 3B. PM2 PP2 BP4_Moderate BP6

The NM_001387283.1(SMARCA4):​c.226A>G​(p.Met76Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,740 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M76T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 2.94

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 0 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=0.19336933).
• BP6: Variant 19-10985276-A-G is Benign according to our data. Variant chr19-10985276-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 470296.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=2, Likely_benign=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMARCA4	NM_001387283.1	c.226A>G	p.Met76Val	missense_variant	3/36	ENST00000646693.2
SMARCA4	NM_003072.5	c.226A>G	p.Met76Val	missense_variant	3/35	ENST00000344626.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMARCA4	ENST00000646693.2	c.226A>G	p.Met76Val	missense_variant	3/36		NM_001387283.1
SMARCA4	ENST00000344626.10	c.226A>G	p.Met76Val	missense_variant	3/35	1	NM_003072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461740 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727174

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Intellectual disability, autosomal dominant 16 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Jul 15, 2021

- -

Rhabdoid tumor predisposition syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 31, 2024

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 76 of the SMARCA4 protein (p.Met76Val). This variant is not present in population databases (gnomAD no frequency). 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: 470296). 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 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

May 23, 2023

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Uncertain	0.035	T
BayesDel_noAF	Benign	-0.19
CADD	Benign	18
DANN	Benign	0.88
DEOGEN2	Benign	0.20	T;.;T;.;.;.;.;.;.;.;T;.;.;.;.;.;.;T;T
Eigen	Benign	-0.50
Eigen_PC	Benign	-0.41
FATHMM_MKL	Uncertain	0.97	D
M_CAP	Uncertain	0.22	D
MetaRNN	Benign	0.19	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.25	T
MutationAssessor	Benign	0.69	N;.;.;.;N;N;.;N;N;N;N;.;N;N;N;N;N;.;.
MutationTaster	Benign	0.98	D;D;D;D;D;D;D;D;D
PrimateAI	Benign	0.46	T
PROVEAN	Benign	-0.24	N;.;.;.;.;.;.;.;.;.;N;.;.;N;.;N;.;N;N
REVEL	Uncertain	0.31
Sift	Uncertain	0.0080	D;.;.;.;.;.;.;.;.;.;D;.;.;D;.;D;.;D;D
Sift4G	Benign	0.46	T;.;.;.;.;.;.;.;.;.;T;.;.;T;T;T;T;T;T
Polyphen		0.0010	B;.;B;.;.;.;.;.;.;.;B;.;.;.;.;.;.;.;B
Vest4		0.50
MutPred		0.12		Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);Gain of helix (P = 0.132);
MVP		0.61
MPC		0.26
ClinPred		0.10	T
GERP RS		3.8
Varity_R		0.22
gMVP		0.24

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: rs1225673675; hg19: chr19-11095952;