rs972229279

Positions:

• chr16-9764005-T-A
• chr16-9764005-T-C
• chr16-9764005-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001134407.3(GRIN2A):​c.3539A>T​(p.Asn1180Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: GRIN2A NM_001134407.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.90

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]

GRIN2A (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.2666422).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GRIN2A	NM_001134407.3	c.3539A>T	p.Asn1180Ile	missense_variant	13/13	ENST00000330684.4	NP_001127879.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GRIN2A	ENST00000330684.4	c.3539A>T	p.Asn1180Ile	missense_variant	13/13	1	NM_001134407.3	ENSP00000332549.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152164 Hom.: 0 Cov.: 32

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 33

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152164 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74340

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: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Landau-Kleffner syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 01, 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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with GRIN2A-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces asparagine with isoleucine at codon 1180 of the GRIN2A protein (p.Asn1180Ile). The asparagine residue is moderately conserved and there is a large physicochemical difference between asparagine and isoleucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.097
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.45
CADD	Benign	17
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.46	T;.;.;T
Eigen	Uncertain	0.21
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.89	.;D;D;D
M_CAP	Benign	0.070	D
MetaRNN	Benign	0.27	T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.9	L;.;L;L
PrimateAI	Benign	0.33	T
PROVEAN	Benign	-0.69	N;.;N;N
REVEL	Benign	0.099
Sift	Uncertain	0.017	D;.;D;D
Sift4G	Uncertain	0.018	D;D;D;D
Polyphen		0.90	P;.;.;P
Vest4		0.41
MutPred		0.48		Gain of sheet (P = 0.0073);.;Gain of sheet (P = 0.0073);Gain of sheet (P = 0.0073);
MVP		0.39
MPC		0.34
ClinPred		0.57	D
GERP RS		5.3
Varity_R		0.25
gMVP		0.23

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: rs972229279; hg19: chr16-9857862;