chr12-13564302-T-A

Position:

• chr12-13564302-T-A

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PP2 PP3_Moderate BS2

The NM_000834.5(GRIN2B):​c.2936A>T​(p.Asn979Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,614,094 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: GRIN2B NM_000834.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.01

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 Likely_benign. Variant got -1 ACMG points.

• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.895
• BS2: High AC in GnomAdExome4 at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GRIN2B	NM_000834.5	c.2936A>T	p.Asn979Ile	missense_variant	14/14	ENST00000609686.4	NP_000825.2
GRIN2B	NM_001413992.1	c.2936A>T	p.Asn979Ile	missense_variant	15/15		NP_001400921.1
GRIN2B	XM_005253351.3	c.722A>T	p.Asn241Ile	missense_variant	4/4		XP_005253408.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GRIN2B	ENST00000609686.4	c.2936A>T	p.Asn979Ile	missense_variant	14/14	1	NM_000834.5	ENSP00000477455.1
GRIN2B	ENST00000637214.1	c.69+44301A>T		intron_variant		5		ENSP00000489997.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152204 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000752 AC: 11 AN: 1461890 Hom.: 0 Cov.: 37 AF XY: 0.00000550 AC XY: 4 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000989

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152204 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74352

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

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

Oct 14, 2021

This sequence change replaces asparagine with isoleucine at codon 979 of the GRIN2B protein (p.Asn979Ile). The asparagine residue is highly conserved and there is a large physicochemical difference between asparagine and isoleucine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with GRIN2B-related conditions. ClinVar contains an entry for this variant (Variation ID: 205714). 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: "Probably Damaging"; Align-GVGD: "Class C0"). 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Sep 29, 2014

p.Asn979Ile (N979I): c.2936 A>T. The N979I variant has not been published as a mutation, nor has it been reported as a benign polymorphism to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The N979I 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. This substitution occurs at a position that is conserved across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. However, missense mutations in nearby residues have not been reported. N979I may be a benign variant, however, the possibility that it is a disease-associated mutation cannot be excluded. The variant is found in EPILEPSY panel(s). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.75	D
Eigen	Pathogenic	0.79
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Benign	0.044	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Benign	-0.85	T
MutationAssessor	Uncertain	2.3	M
PrimateAI	Uncertain	0.68	T
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.71
MutPred		0.75		Gain of sheet (P = 0.0266);
MVP		0.95
MPC		2.6
ClinPred		0.99	D
GERP RS		5.6
Varity_R		0.71
gMVP		0.84

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: rs796052574; hg19: chr12-13717236;