5-178986132-G-T

Variant names:

• chr5-178986132-G-T
• rs62638624
• NM_000843.4:c.2122C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000843.4(GRM6):​c.2122C>A​(p.Gln708Lys) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,822 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. 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. Q708H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: GRM6 NM_000843.4 missense, splice_region
• Scores: Splicing: ADA: 0.7682
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.35
• Publications: 5 publications found

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]

ENSG00000254035 (HGNC:):

ZNF454 (HGNC:21200): (zinc finger protein 454) Enables sequence-specific double-stranded DNA binding activity. Predicted to be involved in regulation of transcription by RNA polymerase II. Predicted to be active in nucleus. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.965

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000843.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GRM6	NM_000843.4	MANE Select	c.2122C>A	p.Gln708Lys	missense splice_region	Exon 9 of 11	NP_000834.2	O15303

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GRM6	ENST00000517717.3	TSL:5 MANE Select	c.2122C>A	p.Gln708Lys	missense splice_region	Exon 9 of 11	ENSP00000430767.1	O15303
	GRM6	ENST00000231188.9	TSL:2	c.2122C>A	p.Gln708Lys	missense splice_region	Exon 8 of 10	ENSP00000231188.5	O15303
	GRM6	ENST00000650031.1		c.2122C>A	p.Gln708Lys	missense splice_region	Exon 10 of 12	ENSP00000497110.1	O15303

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000804 AC: 2 AN: 248740 AF XY: 0.00000741

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000178

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460822 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726654

African (AFR) AF: 0.00 AC: 0 AN: 33458

American (AMR) AF: 0.00 AC: 0 AN: 44666

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26094

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86122

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53354

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5630

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111478

Other (OTH) AF: 0.00 AC: 0 AN: 60332

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.84	T
M_CAP	Uncertain	0.097	D
MetaRNN	Pathogenic	0.97	D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	4.0	H
PhyloP100		9.3
PrimateAI	Uncertain	0.63	T
PROVEAN	Uncertain	-3.8	D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.90
MutPred		0.84		Gain of ubiquitination at Q708 (P = 0.0388)
MVP		0.95
MPC		0.58
ClinPred		0.99	D
GERP RS		5.1
Varity_R		0.90
gMVP		0.71
Mutation Taster		=36/64	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.77
dbscSNV1_RF	Benign	0.69
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: rs62638624; hg19: chr5-178413133;