NM_000834.5:c.3400C>G

Variant names:

• chr12-13563838-G-C
• rs979079013
• NM_000834.5:c.3400C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000834.5(GRIN2B):​c.3400C>G​(p.Leu1134Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 11/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L1134L) has been classified as Benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: GRIN2B NM_000834.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.00
• Publications: 0 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: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2B	NM_000834.5	c.3400C>G	p.Leu1134Val	missense_variant	Exon 14 of 14	ENST00000609686.4	NP_000825.2
GRIN2B	NM_001413992.1	c.3400C>G	p.Leu1134Val	missense_variant	Exon 15 of 15		NP_001400921.1
GRIN2B	XM_005253351.3	c.1186C>G	p.Leu396Val	missense_variant	Exon 4 of 4		XP_005253408.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2B	ENST00000609686.4	c.3400C>G	p.Leu1134Val	missense_variant	Exon 14 of 14	1	NM_000834.5	ENSP00000477455.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal dominant 6;C4015316:Developmental and epileptic encephalopathy, 27 Uncertain:1

Aug 26, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with GRIN2B-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with valine at codon 1134 of the GRIN2B protein (p.Leu1134Val). The leucine residue is moderately conserved and there is a small physicochemical difference between leucine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.082
BayesDel_addAF	Benign	-0.021	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.54	D
Eigen	Benign	0.14
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.0029	T
MetaRNN	Uncertain	0.50	D
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.6	L
PhyloP100		2.0
PrimateAI	Uncertain	0.76	T
Sift4G	Benign	0.38	T
Polyphen		0.67	P
Vest4		0.51
MutPred		0.63		Gain of sheet (P = 0.1208);
MVP		0.46
MPC		1.0
ClinPred		0.80	D
GERP RS		4.6
Varity_R		0.085
gMVP		0.36
Mutation Taster		=95/5	polymorphism

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

Other links and lift over

dbSNP: rs979079013; hg19: chr12-13716772;