rs879253760

Variant names:

• chr16-9849810-AG-A
• rs879253760
• NM_001134407.3:c.1273delC

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_001134407.3(GRIN2A):​c.1273delC​(p.Leu425fs) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. L425L) has been classified as Benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GRIN2A NM_001134407.3 frameshift
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 1.28
• Publications: 0 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-9849810-AG-A is Pathogenic according to our data. Variant chr16-9849810-AG-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 242916.We mark this variant Likely_pathogenic, oryginal submission is: [Conflicting_classifications_of_pathogenicity].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2A	NM_001134407.3	c.1273delC	p.Leu425fs	frameshift_variant	Exon 5 of 13	ENST00000330684.4	NP_001127879.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2A	ENST00000330684.4	c.1273delC	p.Leu425fs	frameshift_variant	Exon 5 of 13	1	NM_001134407.3	ENSP00000332549.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Landau-Kleffner syndrome Pathogenic:1

Mar 29, 2022

Laboratory of Medical Genetics, National & Kapodistrian University of Athens

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PVS1, PM2 -

Intellectual disability Uncertain:1

Feb 24, 2016

Center of Genomic medicine, Geneva, University Hospital of Geneva

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		1.3

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

Other links and lift over

dbSNP: rs879253760; hg19: chr16-9943667;