16-9798268-GGGTCTTACCATCACCCACA-G

Position:

• chr16-9798268-GGGTCTTACCATCACCCACA-G

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PVS1 PM2 PP3 PP5_Very_Strong

The NM_001134407.3(GRIN2A):​c.2346_2356+8del variant causes a splice donor, splice donor 5th base, coding sequence, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GRIN2A NM_001134407.3 splice_donor, splice_donor_5th_base, coding_sequence, intron
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 9.16

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]

(HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 19 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: No computational evidence supports a deleterious effect, but strongly conserved according to phyloP
• PP5: Variant 16-9798268-GGGTCTTACCATCACCCACA-G is Pathogenic according to our data. Variant chr16-9798268-GGGTCTTACCATCACCCACA-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 421444.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRIN2A	NM_001134407.3	c.2346_2356+8del		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	11/13	ENST00000330684.4
LOC105371077	XR_933063.4	n.1076+3547_1076+3565del		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRIN2A	ENST00000330684.4	c.2346_2356+8del		splice_donor_variant, splice_donor_5th_base_variant, coding_sequence_variant, intron_variant	11/13	1	NM_001134407.3	P1
	ENST00000636913.1	n.86+3547_86+3565del		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Landau-Kleffner syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 17, 2017

This variant has not been reported in the literature in individuals with GRIN2A-related disease. 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 is a gross deletion of the genomic region encompassing part of exon 12 of the GRIN2A gene, including the exon 12-intron 12 boundary (c.2346_2356+8del). This is expected to create a premature translational stop signal and result in an absent or disrupted protein product. -

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Oct 11, 2016

A novel c.2346_2356+8del19 variant that is likely pathogenic has been identified in the GRIN2A gene. The c.2346_2356+8del19 variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. This variant results in the deletion of 19 nucleotides at the exon 12/intron 12 boundary including the splice acceptor site and is predicted to cause abnormal gene splicing. However, in the absence of RNA/functional studies, the actual effect of this sequence change in this individual is unknown. Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded. -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1064795143; hg19: chr16-9892125;