16-9849835-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM1

The NM_001134407.3(GRIN2A):​c.1249G>A​(p.Val417Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,613,848 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V417F) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

GRIN2A
NM_001134407.3 missense

Scores

5
6
8

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.81

Publications

9 publications found
Variant links:
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 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • Landau-Kleffner syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • continuous spikes and waves during sleep
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • early-onset epileptic encephalopathy and intellectual disability due to GRIN2A mutation
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • rolandic epilepsy-speech dyspraxia syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • self-limited epilepsy with centrotemporal spikes
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • neurodevelopmental disorder
    Inheritance: AR Classification: LIMITED Submitted by: G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM1
In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 4 uncertain in NM_001134407.3

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GRIN2ANM_001134407.3 linkc.1249G>A p.Val417Ile missense_variant Exon 5 of 13 ENST00000330684.4 NP_001127879.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GRIN2AENST00000330684.4 linkc.1249G>A p.Val417Ile missense_variant Exon 5 of 13 1 NM_001134407.3 ENSP00000332549.3

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152072
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251316
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000547
AC:
8
AN:
1461776
Hom.:
0
Cov.:
33
AF XY:
0.00000825
AC XY:
6
AN XY:
727206
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39692
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111908
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00275900), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.381
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152072
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74272
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41392
American (AMR)
AF:
0.0000655
AC:
1
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Landau-Kleffner syndrome Uncertain:1
Dec 08, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 417 of the GRIN2A protein (p.Val417Ile). This variant is present in population databases (rs749504561, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with GRIN2A-related conditions. ClinVar contains an entry for this variant (Variation ID: 411288). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on GRIN2A protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.36
BayesDel_addAF
Benign
-0.058
T
BayesDel_noAF
Benign
-0.32
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.34
T;.;.;T
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.74
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
1.0
.;D;D;D
M_CAP
Pathogenic
0.61
D
MetaRNN
Uncertain
0.57
D;D;D;D
MetaSVM
Benign
-0.89
T
MutationAssessor
Uncertain
2.8
M;.;M;M
PhyloP100
7.8
PrimateAI
Uncertain
0.68
T
PROVEAN
Benign
-0.98
N;.;N;N
REVEL
Benign
0.17
Sift
Benign
0.19
T;.;T;T
Sift4G
Uncertain
0.057
T;T;T;T
Polyphen
0.99
D;.;.;D
Vest4
0.68
MutPred
0.46
Loss of catalytic residue at V417 (P = 0.0051);.;Loss of catalytic residue at V417 (P = 0.0051);Loss of catalytic residue at V417 (P = 0.0051);
MVP
0.62
MPC
1.4
ClinPred
0.95
D
GERP RS
5.2
Varity_R
0.24
gMVP
0.80
Mutation Taster
=50/50

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

Other links and lift over

dbSNP: rs749504561; hg19: chr16-9943692; COSMIC: COSV58028771; COSMIC: COSV58028771; API