4-157312714-GC-G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001083619.3(GRIA2):c.506del(p.Ala169ValfsTer7) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GRIA2 NM_001083619.3 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.85

Genes affected

GRIA2 (HGNC:4572): (glutamate ionotropic receptor AMPA type subunit 2) Glutamate receptors are the predominant excitatory neurotransmitter receptors in the mammalian brain and are activated in a variety of normal neurophysiologic processes. This gene product belongs to a family of glutamate receptors that are sensitive to alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA), and function as ligand-activated cation channels. These channels are assembled from 4 related subunits, GRIA1-4. The subunit encoded by this gene (GRIA2) is subject to RNA editing (CAG->CGG; Q->R) within the second transmembrane domain, which is thought to render the channel impermeable to Ca(2+). Human and animal studies suggest that pre-mRNA editing is essential for brain function, and defective GRIA2 RNA editing at the Q/R site may be relevant to amyotrophic lateral sclerosis (ALS) etiology. Alternative splicing, resulting in transcript variants encoding different isoforms, (including the flip and flop isoforms that vary in their signal transduction properties), has been noted for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 4-157312714-GC-G is Pathogenic according to our data. Variant chr4-157312714-GC-G is described in ClinVar as [Pathogenic]. Clinvar id is 1698825.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRIA2	NM_001083619.3	c.506del	p.Ala169ValfsTer7	frameshift_variant	4/16	ENST00000264426.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRIA2	ENST00000264426.14	c.506del	p.Ala169ValfsTer7	frameshift_variant	4/16	1	NM_001083619.3	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder with language impairment and behavioral abnormalities Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genetics and Molecular Pathology, SA Pathology

Jan 13, 2022

The GRIA2 c.506del variant is classified as PATHOGENIC (PM2, PS2, PVS1) This GRIA2 c.506del variant is located in exon 4/16 and is predicted to cause a shift in the reading frame at codon 169 (PVS1). This variant is de novo in this individual (PS2). This variant has not been reported in dbSNP and is absent from population databases (PM2). It has not been reported in the ClinVar or HGMD disease databases. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-158233866;