rs281875191

Variant names:

• chr9-2081914-C-T
• rs281875191
• NM_003070.5:c.2267C>T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_003070.5(SMARCA2):​c.2267C>T​(p.Thr756Ile) 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. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMARCA2 NM_003070.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2 O:1
• Conservation: PhyloP100: 7.91

Genes affected

SMARCA2 (HGNC:11098): (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 2) The protein encoded by this gene is a member of the SWI/SNF family of proteins and is highly 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. Alternatively spliced transcript variants encoding different isoforms have been found for this gene, which contains a trinucleotide repeat (CAG) length polymorphism. [provided by RefSeq, Jan 2014]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a domain Helicase ATP-binding (size 165) in uniprot entity SMCA2_HUMAN there are 28 pathogenic changes around while only 0 benign (100%) in NM_003070.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the SMARCA2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 93 curated pathogenic missense variants (we use a threshold of 10). The gene has 88 curated benign missense variants. Gene score misZ: 5.054 (above the threshold of 3.09). Trascript score misZ: 4.663 (above the threshold of 3.09). GenCC associations: The gene is linked to intellectual disability-sparse hair-brachydactyly syndrome, Coffin-Siris syndrome 1.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMARCA2	NM_003070.5	c.2267C>T	p.Thr756Ile	missense_variant	Exon 15 of 34	ENST00000349721.8	NP_003061.3
SMARCA2	NM_001289396.2	c.2267C>T	p.Thr756Ile	missense_variant	Exon 15 of 34		NP_001276325.1
SMARCA2	NM_139045.4	c.2267C>T	p.Thr756Ile	missense_variant	Exon 15 of 33		NP_620614.2
SMARCA2	NM_001289397.2	c.2267C>T	p.Thr756Ile	missense_variant	Exon 15 of 33		NP_001276326.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMARCA2	ENST00000349721.8	c.2267C>T	p.Thr756Ile	missense_variant	Exon 15 of 34	5	NM_003070.5	ENSP00000265773.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Nicolaides-Baraitser syndrome Uncertain:1

Sep 01, 2017

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Likely pathogenicity based on finding it once in our laboratory de novo in a 9-year-old female with global delays with regression, autism, epilepsy, dymorphisms, short stature, joint laxity, scoliosis, hypohydrosis, thin hair, significant myopia -

SMARCA2-related BAFopathy Uncertain:1

Jun 10, 2021

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Other:1

-

UniProtKB/Swiss-Prot

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	27
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	.;.;D;.;D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.99
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.99	.;D;.;D;D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	4.7	H;.;H;H;H
PrimateAI	Pathogenic	0.94	D
PROVEAN	Pathogenic	-5.7	D;.;D;D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;.;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Polyphen		1.0	D;.;D;D;D
Vest4		0.99
MutPred		0.92		Loss of catalytic residue at T756 (P = 0.1782);Loss of catalytic residue at T756 (P = 0.1782);Loss of catalytic residue at T756 (P = 0.1782);Loss of catalytic residue at T756 (P = 0.1782);Loss of catalytic residue at T756 (P = 0.1782);
MVP		0.98
MPC		2.4
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.94
gMVP		0.99

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: rs281875191; hg19: chr9-2081914;