chr7-126533073-G-A

Position:

chr7-126533073-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000845.3(GRM8):c.2309C>T(p.Thr770Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,613,112 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 30)

Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

GRM8
NM_000845.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 10.0

Variant links:

Genes affected

GRM8 (HGNC:4600): (glutamate metabotropic receptor 8) L-glutamate is the major excitatory neurotransmitter in the central nervous system and activates both ionotropic and metabotropic glutamate receptors. Glutamatergic neurotransmission is involved in most aspects of normal brain function and can be perturbed in many neuropathologic conditions. The metabotropic glutamate receptors are a family of G protein-coupled receptors, that have been divided into 3 groups on the basis of sequence homology, putative signal transduction mechanisms, and pharmacologic properties. Group I includes GRM1 and GRM5 and these receptors have been shown to activate phospholipase C. Group II includes GRM2 and GRM3 while Group III includes GRM4, GRM6, GRM7 and GRM8. Group II and III receptors are linked to the inhibition of the cyclic AMP cascade but differ in their agonist selectivities. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2008]

GRM8 links:

LOC101928357 (HGNC:):

LOC101928357 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.961

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRM8	NM_000845.3 linkuse as main transcript	c.2309C>T	p.Thr770Met	missense_variant	9/11	ENST00000339582.7
LOC101928357	XR_927937.3 linkuse as main transcript	n.215-1679G>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRM8	ENST00000339582.7 linkuse as main transcript	c.2309C>T	p.Thr770Met	missense_variant	9/11	5	NM_000845.3	P1	O00222-1

Frequencies

GnomAD3 genomes

AF:

0.0000462

AC:

AN:

151608

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000727

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000589

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251144

Hom.:

AF XY:

0.00000737

AC XY:

AN XY:

135724

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000958

AC:

AN:

1461504

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727090

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000224

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:

0.0000108

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000462

AC:

AN:

151608

Hom.:

Cov.:

AF XY:

0.0000541

AC XY:

AN XY:

73968

show subpopulations

Gnomad4 AFR

AF:

0.0000727

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000589

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000142

Hom.:

Bravo

AF:

0.0000264

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.00

AC:

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2023

The c.2309C>T (p.T770M) alteration is located in exon 9 (coding exon 8) of the GRM8 gene. This alteration results from a C to T substitution at nucleotide position 2309, causing the threonine (T) at amino acid position 770 to be replaced by a methionine (M). 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

Pathogenic

0.86

BayesDel_addAF

Pathogenic

0.33

BayesDel_noAF

Pathogenic

0.42

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.90

D;.;.

Eigen

Pathogenic

0.88

Eigen_PC

Pathogenic

0.82

FATHMM_MKL

Uncertain

0.95

LIST_S2

Pathogenic

0.97

D;.;D

M_CAP

Uncertain

0.27

MetaRNN

Pathogenic

0.96

D;D;D

MetaSVM

Pathogenic

0.90

MutationAssessor

Pathogenic

3.3

M;M;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Pathogenic

0.90

PROVEAN

Pathogenic

-5.2

D;D;.

REVEL

Pathogenic

0.82

Sift

Pathogenic

0.0

D;D;.

Sift4G

Pathogenic

0.0

D;D;D

Polyphen

1.0

D;D;.

Vest4

0.92

MutPred

0.88

Loss of methylation at K769 (P = 0.0384);Loss of methylation at K769 (P = 0.0384);.;

MVP

0.84

MPC

0.79

ClinPred

0.99

GERP RS

4.8

Varity_R

0.82

gMVP

0.94

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over