chr12-13563823-T-C

Position:

• chr12-13563823-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_000834.5(GRIN2B):​c.3415A>G​(p.Thr1139Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,838 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: GRIN2B NM_000834.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.655

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 Uncertain_significance. Variant got 1 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), GRIN2B. . Gene score misZ 5.4168 (greater than the threshold 3.09). Trascript score misZ 7.3273 (greater than threshold 3.09). GenCC has associacion of gene with autism susceptibility 1, developmental and epileptic encephalopathy, 27, autosomal dominant non-syndromic intellectual disability, complex neurodevelopmental disorder, West syndrome, intellectual disability, autosomal dominant 6.
• BP4: Computational evidence support a benign effect (MetaRNN=0.09458879).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GRIN2B	NM_000834.5	c.3415A>G	p.Thr1139Ala	missense_variant	14/14	ENST00000609686.4	NP_000825.2
GRIN2B	NM_001413992.1	c.3415A>G	p.Thr1139Ala	missense_variant	15/15		NP_001400921.1
GRIN2B	XM_005253351.3	c.1201A>G	p.Thr401Ala	missense_variant	4/4		XP_005253408.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GRIN2B	ENST00000609686.4	c.3415A>G	p.Thr1139Ala	missense_variant	14/14	1	NM_000834.5	ENSP00000477455	P1
GRIN2B	ENST00000637214.1	c.69+44780A>G		intron_variant		5		ENSP00000489997

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461838 Hom.: 0 Cov.: 37 AF XY: 0.00000413 AC XY: 3 AN XY: 727226

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 20, 2018

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 output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The alanine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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 threonine with alanine at codon 1139 of the GRIN2B protein (p.Thr1139Ala). The threonine residue is moderately conserved and there is a small physicochemical difference between threonine and alanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.057
BayesDel_addAF	Benign	-0.31	T
BayesDel_noAF	Benign	-0.68
CADD	Benign	0.093
DANN	Benign	0.73
DEOGEN2	Benign	0.38	T
Eigen	Benign	-1.3
Eigen_PC	Benign	-1.3
FATHMM_MKL	Benign	0.067	N
LIST_S2	Benign	0.66	T
M_CAP	Benign	0.0011	T
MetaRNN	Benign	0.095	T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	-0.67	N
MutationTaster	Benign	0.99	N
PrimateAI	Benign	0.45	T
Sift4G	Benign	0.60	T
Polyphen		0.0	B
Vest4		0.046
MutPred		0.47		Loss of phosphorylation at T1139 (P = 0.0394);
MVP		0.40
MPC		0.58
ClinPred		0.098	T
GERP RS		-6.7
Varity_R		0.048
gMVP		0.11

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: rs200237781; hg19: chr12-13716757;