chr5-178981725-G-A

Position:

chr5-178981725-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_000843.4(GRM6):c.2566C>T(p.Arg856Trp) variant causes a missense change. The variant allele was found at a frequency of 0.000123 in 1,613,912 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R856Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000079 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00013 ( 0 hom. )

Consequence

GRM6
NM_000843.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.11

Variant links:

Genes affected

GRM6 (HGNC:4598): (glutamate metabotropic receptor 6) 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. Mutations in this gene result in congenital stationary night blindness type 1B. [provided by RefSeq, May 2018]

GRM6 links:

(HGNC:):

links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.799

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GRM6	NM_000843.4 linkuse as main transcript	c.2566C>T	p.Arg856Trp	missense_variant	11/11	ENST00000517717.3
ZNF454	XR_007058600.1 linkuse as main transcript	n.5644-8022G>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GRM6	ENST00000517717.3 linkuse as main transcript	c.2566C>T	p.Arg856Trp	missense_variant	11/11	5	NM_000843.4	P1
	ENST00000519491.1 linkuse as main transcript	n.305-8022G>A		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes

AF:

0.0000788

AC:

AN:

152194

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

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:

0.000162

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000358

AC:

AN:

251194

Hom.:

AF XY:

0.0000515

AC XY:

AN XY:

135796

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

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:

0.0000793

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000128

AC:

187

AN:

1461718

Hom.:

Cov.:

AF XY:

0.000131

AC XY:

AN XY:

727188

show subpopulations

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:

0.000164

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.0000788

AC:

AN:

152194

Hom.:

Cov.:

AF XY:

0.0000807

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000162

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000124

Hom.:

Bravo

AF:

0.0000718

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000778

AC:

ExAC

AF:

0.0000494

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 17, 2024

The c.2566C>T (p.R856W) alteration is located in exon 10 (coding exon 10) of the GRM6 gene. This alteration results from a C to T substitution at nucleotide position 2566, causing the arginine (R) at amino acid position 856 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 13, 2022

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 856 of the GRM6 protein (p.Arg856Trp). This variant is present in population databases (rs202022128, gnomAD 0.008%). This variant has not been reported in the literature in individuals affected with GRM6-related conditions. ClinVar contains an entry for this variant (Variation ID: 966276). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt GRM6 protein function. 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

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.30

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.32

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.47

T;T;T

Eigen

Uncertain

0.46

Eigen_PC

Uncertain

0.49

FATHMM_MKL

Uncertain

0.97

LIST_S2

Pathogenic

0.99

D;.;.

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.80

D;D;D

MetaSVM

Uncertain

0.49

MutationAssessor

Benign

1.5

L;L;L

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.58

PROVEAN

Uncertain

-3.2

D;D;.

REVEL

Pathogenic

0.65

Sift

Uncertain

0.0080

D;D;.

Sift4G

Benign

0.11

T;T;.

Polyphen

1.0

D;D;D

Vest4

0.66

MVP

0.86

MPC

0.52

ClinPred

0.86

GERP RS

5.5

Varity_R

0.33

gMVP

0.42

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