rs1057524089

Positions:

• chr16-9938479-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001134407.3(GRIN2A):​c.487C>T​(p.Gln163*) variant causes a stop gained change. The variant allele was found at a frequency of 0.000000684 in 1,460,934 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GRIN2A NM_001134407.3 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.12

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 Pathogenic. Variant got 18 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 16-9938479-G-A is Pathogenic according to our data. Variant chr16-9938479-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 391457.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-9938479-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GRIN2A	NM_001134407.3	c.487C>T	p.Gln163*	stop_gained	3/13	ENST00000330684.4	NP_001127879.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GRIN2A	ENST00000330684.4	c.487C>T	p.Gln163*	stop_gained	3/13	1	NM_001134407.3	ENSP00000332549.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460934 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 726796

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Landau-Kleffner syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	research	Institute of Human Genetics, University of Leipzig Medical Center	Jan 01, 2019	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 01, 2020	For these reasons, this variant has been classified as Pathogenic. Loss-of-function variants in GRIN2A are known to be pathogenic (PMID: 23933819, 23933820). This variant has not been reported in the literature in individuals with GRIN2A-related disease. ClinVar contains an entry for this variant (Variation ID: 391457). This variant is not present in population databases (ExAC no frequency). This sequence change creates a premature translational stop signal (p.Gln163*) in the GRIN2A gene. It is expected to result in an absent or disrupted protein product. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 14, 2016

The Q163X nonsense variant in the GRIN2A gene is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The Q163X variant is not observed in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). Although this pathogenic variant has not been reported previously to our knowledge, its presence is consistent with a diagnosis of GRIN2A-related disorder -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	38
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Uncertain	0.96	D
Vest4		0.88
GERP RS		5.3

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

Publications

LitVar

Other links and lift over

dbSNP: rs1057524089; hg19: chr16-10032336;