chr12-13570019-T-C

Variant names:

• chr12-13570019-T-C
• rs398122824
• NM_000834.5:c.2172-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000834.5(GRIN2B):​c.2172-2A>G variant causes a splice acceptor, intron 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: GRIN2B NM_000834.5 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 8.01
• Publications: 7 publications found

Genes affected

GRIN2B (HGNC:4586): (glutamate ionotropic receptor NMDA type subunit 2B) This gene encodes a member of the N-methyl-D-aspartate (NMDA) receptor family within the ionotropic glutamate receptor superfamily. The encoded protein is a subunit of the NMDA receptor ion channel which acts as an agonist binding site for glutamate. The NMDA receptors mediate a slow calcium-permeable component of excitatory synaptic transmission in the central nervous system. The NMDA receptors are heterotetramers of seven genetically encoded, differentially expressed subunits including NR1 (GRIN1), NR2 (GRIN2A, GRIN2B, GRIN2C, or GRIN2D) and NR3 (GRIN3A or GRIN3B). The early expression of this gene in development suggests a role in brain development, circuit formation, synaptic plasticity, and cellular migration and differentiation. Naturally occurring mutations within this gene are associated with neurodevelopmental disorders including autism spectrum disorder, attention deficit hyperactivity disorder, epilepsy, and schizophrenia. [provided by RefSeq, Aug 2017]

GRIN2B Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics
• developmental and epileptic encephalopathy, 27

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• intellectual disability, autosomal dominant 6

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• autosomal dominant non-syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 5.1, offset of 29, new splice context is: tgccttcatctatgatgcAGcag. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-13570019-T-C is Pathogenic according to our data. Variant chr12-13570019-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 39659.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2B	NM_000834.5	c.2172-2A>G		splice_acceptor_variant, intron_variant	Intron 11 of 13	ENST00000609686.4	NP_000825.2
GRIN2B	NM_001413992.1	c.2172-2A>G		splice_acceptor_variant, intron_variant	Intron 12 of 14		NP_001400921.1
GRIN2B	XM_005253351.3	c.-43-2A>G		splice_acceptor_variant, intron_variant	Intron 1 of 3		XP_005253408.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2B	ENST00000609686.4	c.2172-2A>G		splice_acceptor_variant, intron_variant	Intron 11 of 13	1	NM_000834.5	ENSP00000477455.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Intellectual disability, autosomal dominant 6 Pathogenic:3

Sep 01, 2020

Breda Genetics srl

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The variant c.2172-2A>G in the GRIN2B gene is reported as pathogenic for autosomal dominant mental retardation 6 in ClinVar (Variation ID: 39659). The variant affects the acceptor splice site of intron 10 and is therefore highly likely to impact the splicing process by causing the exclusion of the following exons from the mature transcript and the translation of an aberrant protein or a shift in the reading frame. There is no information on frequency in gnomAD, 1000 Genomes or NHLI Exome Sequencing Project (ESP). The c.2172-2A>G de novo pathogenic variant has already been reported by O’Roak et al. (2012) in a patient with autism, a nonverbal IQ of 65 and developmental regression (PMID: 23160955). -

Dec 21, 2012

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Apr 04, 2017

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was identified as de novo (maternity and paternity confirmed). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.050
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Uncertain	0.95	D
PhyloP100		8.0
GERP RS		5.6
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.92
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.56		Position offset: -31
DS_AL_spliceai		1.0		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs398122824; hg19: chr12-13722953;