12-13562800-TA-T

Variant names:

• chr12-13562800-TA-T
• rs1948563428
• NM_000834.5:c.4437delT

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_000834.5(GRIN2B):​c.4437delT​(p.Ser1479ArgfsTer8) 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: GRIN2B NM_000834.5 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.76

Genes affected

GRIN2B (HGNC:4586): (glutamate ionotropic receptor NMDA type subunit 2B) This gene encodes a member of the N-methyl-D-aspartate (NMDA) receptor family within the ionotropic glutamate receptor superfamily. The encoded protein is a subunit of the NMDA receptor ion channel which acts as an agonist binding site for glutamate. The NMDA receptors mediate a slow calcium-permeable component of excitatory synaptic transmission in the central nervous system. The NMDA receptors are heterotetramers of seven genetically encoded, differentially expressed subunits including NR1 (GRIN1), NR2 (GRIN2A, GRIN2B, GRIN2C, or GRIN2D) and NR3 (GRIN3A or GRIN3B). The early expression of this gene in development suggests a role in brain development, circuit formation, synaptic plasticity, and cellular migration and differentiation. Naturally occurring mutations within this gene are associated with neurodevelopmental disorders including autism spectrum disorder, attention deficit hyperactivity disorder, epilepsy, and schizophrenia. [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00404 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2B	NM_000834.5	c.4437delT	p.Ser1479ArgfsTer8	frameshift_variant	Exon 14 of 14	ENST00000609686.4	NP_000825.2
GRIN2B	NM_001413992.1	c.4437delT	p.Ser1479ArgfsTer8	frameshift_variant	Exon 15 of 15		NP_001400921.1
GRIN2B	XM_005253351.3	c.2223delT	p.Ser741ArgfsTer8	frameshift_variant	Exon 4 of 4		XP_005253408.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2B	ENST00000609686.4	c.4437delT	p.Ser1479ArgfsTer8	frameshift_variant	Exon 14 of 14	1	NM_000834.5	ENSP00000477455.1
GRIN2B	ENST00000637214.1	c.69+45802delT		intron_variant	Intron 1 of 1	5		ENSP00000489997.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal dominant 6;C4015316:Developmental and epileptic encephalopathy, 27 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 22, 2022

This sequence change results in a frameshift in the GRIN2B gene (p.Ser1479Argfs*8). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 6 amino acid(s) of the GRIN2B protein and extend the protein by 1 additional amino acid residues. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with GRIN2B-related conditions. ClinVar contains an entry for this variant (Variation ID: 856799). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs1948563428; hg19: chr12-13715734;