rs1060502100

Positions:

• chr19-11039540-C-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.4253C>T​(p.Thr1418Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000691 in 1,446,168 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 8/12 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SMARCA4 NM_001387283.1 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 0.603

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 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=0.16238046).
• BP6: Variant 19-11039540-C-T is Benign according to our data. Variant chr19-11039540-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 408693.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SMARCA4	NM_001387283.1	c.4253C>T	p.Thr1418Ile	missense_variant	30/36	ENST00000646693.2	NP_001374212.1
SMARCA4	NM_003072.5	c.4171-1767C>T		intron_variant		ENST00000344626.10	NP_003063.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SMARCA4	ENST00000646693.2	c.4253C>T	p.Thr1418Ile	missense_variant	30/36		NM_001387283.1	ENSP00000495368
SMARCA4	ENST00000344626.10	c.4171-1767C>T		intron_variant		1	NM_003072.5	ENSP00000343896	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.91e-7 AC: 1 AN: 1446168 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 719024

Gnomad4 AFR exome AF: 0.0000307

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Rhabdoid tumor predisposition syndrome 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 09, 2023

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. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. ClinVar contains an entry for this variant (Variation ID: 408693). 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 isoleucine, which is neutral and non-polar, at codon 1418 of the SMARCA4 protein (p.Thr1418Ile). -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 28, 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
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.60
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Benign	0.011	.;T;.;.;T
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.74
FATHMM_MKL	Benign	0.0064	N
LIST_S2	Benign	0.66	T;.;.;T;T
M_CAP	Uncertain	0.25	D
MetaRNN	Benign	0.16	T;T;T;T;T
MetaSVM	Benign	-0.58	T
MutationTaster	Benign	1.0	N;N;N;N;N;N;N;N;N
PrimateAI	Uncertain	0.65	T
Sift4G	Benign	0.18	.;.;.;.;T
Polyphen		0.82	.;P;.;.;P
Vest4		0.26
MutPred		0.34		.;Loss of phosphorylation at T1418 (P = 0.028);.;.;Loss of phosphorylation at T1418 (P = 0.028);
MVP		0.13
ClinPred		0.32	T
GERP RS		0.73

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: rs1060502100; hg19: chr19-11150216;