chr6-101818431-C-G

Variant names:

• chr6-101818431-C-G
• rs751662930
• NM_021956.5:c.1265C>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_021956.5(GRIK2):​c.1265C>G​(p.Ala422Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A422V) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: GRIK2 NM_021956.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.56
• Publications: 0 publications found

Genes affected

GRIK2 (HGNC:4580): (glutamate ionotropic receptor kainate 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 the kainate family of glutamate receptors, which are composed of four subunits and function as ligand-activated ion channels. The subunit encoded by this gene is subject to RNA editing at multiple sites within the first and second transmembrane domains, which is thought to alter the structure and function of the receptor complex. Alternatively spliced transcript variants encoding different isoforms have also been described for this gene. Mutations in this gene have been associated with autosomal recessive cognitive disability. [provided by RefSeq, Jul 2008]

GRIK2 Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AR, AD Classification: DEFINITIVE, MODERATE Submitted by: ClinGen
• intellectual disability, autosomal recessive 6

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
• neurodevelopmental disorder with impaired language and ataxia and with or without seizures

  Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• autosomal recessive non-syndromic intellectual disability

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.19946176).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021956.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GRIK2	NM_021956.5	MANE Select	c.1265C>G	p.Ala422Gly	missense	Exon 10 of 17	NP_068775.1
	GRIK2	NM_001166247.1		c.1265C>G	p.Ala422Gly	missense	Exon 9 of 17	NP_001159719.1
	GRIK2	NM_175768.3		c.1265C>G	p.Ala422Gly	missense	Exon 9 of 17	NP_786944.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GRIK2	ENST00000369134.9	TSL:5 MANE Select	c.1265C>G	p.Ala422Gly	missense	Exon 10 of 17	ENSP00000358130.6
	GRIK2	ENST00000421544.6	TSL:1	c.1265C>G	p.Ala422Gly	missense	Exon 12 of 19	ENSP00000397026.1
	GRIK2	ENST00000369138.5	TSL:1	c.1265C>G	p.Ala422Gly	missense	Exon 9 of 17	ENSP00000358134.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 28

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.081
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.50
CADD	Uncertain	24
DANN	Benign	0.92
DEOGEN2	Benign	0.089	T
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.20
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.0080	T
MetaRNN	Benign	0.20	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.035	N
PhyloP100		7.6
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-1.1	N
REVEL	Benign	0.10
Sift	Benign	0.39	T
Sift4G	Benign	0.38	T
Polyphen		0.010	B
Vest4		0.27
MutPred		0.31		Gain of relative solvent accessibility (P = 0.0479)
MVP		0.37
MPC		0.35
ClinPred		0.74	D
GERP RS		4.7
Varity_R		0.17
gMVP		0.41
Mutation Taster		=76/24	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: rs751662930; hg19: chr6-102266306; COSMIC: COSV59723113;