rs749504561

Positions:

• chr16-9849835-C-A
• chr16-9849835-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_001134407.3(GRIN2A):​c.1249G>T​(p.Val417Phe) 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. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V417I) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GRIN2A NM_001134407.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.81

Genes affected

GRIN2A (HGNC:4585): (glutamate ionotropic receptor NMDA type subunit 2A) This gene encodes a member of the glutamate-gated ion channel protein family. The encoded protein is an N-methyl-D-aspartate (NMDA) receptor subunit. NMDA receptors are both ligand-gated and voltage-dependent, and are involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. These receptors are permeable to calcium ions, and activation results in a calcium influx into post-synaptic cells, which results in the activation of several signaling cascades. Disruption of this gene is associated with focal epilepsy and speech disorder with or without cognitive disability. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 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), GRIN2A. . Gene score misZ 2.8278 (greater than the threshold 3.09). Trascript score misZ 3.7088 (greater than threshold 3.09). GenCC has associacion of gene with early-onset epileptic encephalopathy and intellectual disability due to GRIN2A mutation, Landau-Kleffner syndrome, continuous spikes and waves during sleep, complex neurodevelopmental disorder, rolandic epilepsy-speech dyspraxia syndrome, childhood epilepsy with centrotemporal spikes.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.894

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRIN2A	NM_001134407.3	c.1249G>T	p.Val417Phe	missense_variant	5/13	ENST00000330684.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRIN2A	ENST00000330684.4	c.1249G>T	p.Val417Phe	missense_variant	5/13	1	NM_001134407.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 24, 2017

The p.V417F variant (also known as c.1249G>T), located in coding exon 4 of the GRIN2A gene, results from a G to T substitution at nucleotide position 1249. The valine at codon 417 is replaced by phenylalanine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;.;.;D
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	.;D;D;D
M_CAP	Pathogenic	0.91	D
MetaRNN	Pathogenic	0.89	D;D;D;D
MetaSVM	Benign	-0.63	T
MutationAssessor	Uncertain	2.8	M;.;M;M
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Pathogenic	0.79	T
PROVEAN	Pathogenic	-4.9	D;.;D;D
REVEL	Uncertain	0.48
Sift	Pathogenic	0.0	D;.;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;.;.;D
Vest4		0.78
MutPred		0.53		Loss of sheet (P = 0.0126);.;Loss of sheet (P = 0.0126);Loss of sheet (P = 0.0126);
MVP		0.70
MPC		1.8
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.90
gMVP		0.99

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: rs749504561; hg19: chr16-9943692;