rs886052519

Variant names:

• chr16-9754993-T-C
• rs886052519
• NM_001134407.3:c.*8156A>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001134407.3(GRIN2A):​c.*8156A>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000019 in 52,640 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000019 (0 hom.)
• Consequence: GRIN2A NM_001134407.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.543
• 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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.48).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2A	NM_001134407.3	c.*8156A>G		3_prime_UTR_variant	Exon 13 of 13	ENST00000330684.4	NP_001127879.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2A	ENST00000330684.4	c.*8156A>G		3_prime_UTR_variant	Exon 13 of 13	1	NM_001134407.3	ENSP00000332549.3
GRIN2A	ENST00000396573.6	c.*8156A>G		3_prime_UTR_variant	Exon 14 of 14	1		ENSP00000379818.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.0000190 AC: 1 AN: 52640 Hom.: 0 Cov.: 0 AF XY: 0.0000410 AC XY: 1 AN XY: 24402

African (AFR) AF: 0.00 AC: 0 AN: 2296

American (AMR) AF: 0.00 AC: 0 AN: 1530

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3316

East Asian (EAS) AF: 0.00 AC: 0 AN: 8232

South Asian (SAS) AF: 0.00226 AC: 1 AN: 442

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 26

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 354

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 32046

Other (OTH) AF: 0.00 AC: 0 AN: 4398

GnomAD4 genome Cov.: 32

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Landau-Kleffner syndrome Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.48
CADD	Benign	11
DANN	Benign	0.84
PhyloP100		0.54
Mutation Taster		=99/1	polymorphism

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: rs886052519; hg19: chr16-9848850;