rs1555103150

chr12-13567165-C-Gchr12-13567165-C-T

Variant summary

Our verdict is Pathogenic. Variant got 21 ACMG points: 21P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_000834.5(GRIN2B):c.2458G>C(p.Gly820Arg) 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. 11/18 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G820A) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: GRIN2B NM_000834.5 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.90

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]

ACMG classification

Verdict is Pathogenic. Variant got 21 ACMG points.

• PS1: Transcript NM_000834.5 (GRIN2B) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar as 521172
• PM1: In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000834.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-13567164-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 208643.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant where missense usually causes diseases, GRIN2B
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 12-13567165-C-G is Pathogenic according to our data. Variant chr12-13567165-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 546296.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRIN2B	NM_000834.5	c.2458G>C	p.Gly820Arg	missense_variant	13/14	ENST00000609686.4
GRIN2B	NM_001413992.1	c.2458G>C	p.Gly820Arg	missense_variant	14/15
GRIN2B	XM_005253351.3	c.244G>C	p.Gly82Arg	missense_variant	3/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRIN2B	ENST00000609686.4	c.2458G>C	p.Gly820Arg	missense_variant	13/14	1	NM_000834.5	P1
GRIN2B	ENST00000637214.1	c.69+41438G>C		intron_variant		5
GRIN2B	ENST00000628166.2	n.718G>C		non_coding_transcript_exon_variant	5/5	5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

May 23, 2018

The G820R variant in the GRIN2B gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. However, multiple missense variants at this same codon (G820A, G820E, and G820V) have been identified in individuals with GRIN2B-related disorders previously tested at GeneDx and reported in the literature (Deciphering Developmental Disorders Study, 2017; Platzer et al., 2017; Yoo et al., 2017; Hamdan et al., 2014). The G820R variant is not observed in large population cohorts (Lek et al., 2016). The G820R variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. In silico analyses, including protein predictors and evolutionary conservation, support a deleterious effect. The G820R variant occurs within the M4 domain (Swanger et al., 2016). We interpret G820R as a pathogenic variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
Cadd	Pathogenic	31
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.96	D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.71
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.85	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	-0.14	T
MutationAssessor	Pathogenic	3.8	H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.94	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.87		Gain of methylation at G820 (P = 0.039);
MVP		0.96
MPC		2.6
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.96
gMVP		1.0

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: rs1555103150; hg19: chr12-13720099;