4-92304718-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001510.4(GRID2):c.62C>A(p.Ala21Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,452 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A21V) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GRID2 NM_001510.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.25

Genes affected

GRID2 (HGNC:4576): (glutamate ionotropic receptor delta type subunit 2) The protein encoded by this gene is a member of the family of ionotropic glutamate receptors which are the predominant excitatory neurotransmitter receptors in the mammalian brain. The encoded protein is a multi-pass membrane protein that is expressed selectively in cerebellar Purkinje cells. A point mutation in the mouse ortholog, associated with the phenotype named 'lurcher', in the heterozygous state leads to ataxia resulting from selective, cell-autonomous apoptosis of cerebellar Purkinje cells during postnatal development. Mice homozygous for this mutation die shortly after birth from massive loss of mid- and hindbrain neurons during late embryogenesis. This protein also plays a role in synapse organization between parallel fibers and Purkinje cells. Alternate splicing results in multiple transcript variants encoding distinct isoforms. Mutations in this gene cause cerebellar ataxia in humans. [provided by RefSeq, Apr 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.2712409).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRID2	NM_001510.4	c.62C>A	p.Ala21Glu	missense_variant	1/16	ENST00000282020.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRID2	ENST00000282020.9	c.62C>A	p.Ala21Glu	missense_variant	1/16	1	NM_001510.4	P1
GRID2	ENST00000510992.5	c.62C>A	p.Ala21Glu	missense_variant	1/15	1
GRID2	ENST00000505687.5	n.234C>A		non_coding_transcript_exon_variant	1/6	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460452 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726600

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 11, 2022

The c.62C>A (p.A21E) alteration is located in exon 1 (coding exon 1) of the GRID2 gene. This alteration results from a C to A substitution at nucleotide position 62, causing the alanine (A) at amino acid position 21 to be replaced by a glutamic acid (E). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Benign	-0.14	T
BayesDel_noAF	Benign	-0.44
Cadd	Benign	22
Dann	Uncertain	0.99
DEOGEN2	Benign	0.15	T;.
Eigen	Benign	-0.47
Eigen_PC	Benign	-0.33
FATHMM_MKL	Benign	0.57	D
LIST_S2	Benign	0.63	T;T
M_CAP	Benign	0.0088	T
MetaRNN	Benign	0.27	T;T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	0.55	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Uncertain	0.66	T
PROVEAN	Benign	-1.1	N;N
REVEL	Benign	0.083
Sift	Uncertain	0.010	D;D
Sift4G	Uncertain	0.012	D;D
Polyphen		0.013	B;.
Vest4		0.54
MutPred		0.46		Gain of solvent accessibility (P = 0.0016);Gain of solvent accessibility (P = 0.0016);
MVP		0.32
MPC		0.60
ClinPred		0.43	T
GERP RS		2.6
Varity_R		0.16
gMVP		0.44

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: chr4-93225869;