chr6-146399101-G-A

Variant names:

• chr6-146399101-G-A
• rs965990929
• NM_001278064.2:c.2062G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001278064.2(GRM1):​c.2062G>A​(p.Gly688Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,874 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GRM1 NM_001278064.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.19
• Publications: 0 publications found

Genes affected

GRM1 (HGNC:4593): (glutamate metabotropic receptor 1) This gene encodes a metabotropic glutamate receptor that functions by activating phospholipase C. 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 canonical alpha isoform of the encoded protein is a disulfide-linked homodimer whose activity is mediated by a G-protein-coupled phosphatidylinositol-calcium second messenger system. This gene may be associated with many disease states, including schizophrenia, bipolar disorder, depression, and breast cancer. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, May 2013]

GRM1 Gene-Disease associations (from GenCC):

• spinocerebellar ataxia 44

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• autosomal recessive spinocerebellar ataxia 13

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.761

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001278064.2. 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
	GRM1	NM_001278064.2	MANE Select	c.2062G>A	p.Gly688Ser	missense	Exon 7 of 8	NP_001264993.1
	GRM1	NM_001278067.1		c.2062G>A	p.Gly688Ser	missense	Exon 7 of 8	NP_001264996.1
	GRM1	NM_001278065.2		c.2062G>A	p.Gly688Ser	missense	Exon 8 of 10	NP_001264994.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GRM1	ENST00000282753.6	TSL:1 MANE Select	c.2062G>A	p.Gly688Ser	missense	Exon 7 of 8	ENSP00000282753.1
	GRM1	ENST00000355289.8	TSL:1	c.2062G>A	p.Gly688Ser	missense	Exon 7 of 8	ENSP00000347437.4
	GRM1	ENST00000492807.6	TSL:1	c.2062G>A	p.Gly688Ser	missense	Exon 8 of 10	ENSP00000424095.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251316 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS 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: 0.00000137 AC: 2 AN: 1461874 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727236

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000447 AC: 2 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111994

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000203476), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

May 09, 2018

Athena Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.87
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.64	D
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.11	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Uncertain	0.33	D
MutationAssessor	Benign	1.2	L
PhyloP100		8.2
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-5.0	D
REVEL	Pathogenic	0.70
Sift	Benign	0.25	T
Sift4G	Benign	0.14	T
Polyphen		1.0	D
Vest4		0.76
MutPred		0.40		Gain of glycosylation at G688 (P = 0.0411)
MVP		0.79
MPC		1.7
ClinPred		0.98	D
GERP RS		5.5
Varity_R		0.70
gMVP		0.86
Mutation Taster		=48/52	disease causing

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: rs965990929; hg19: chr6-146720237;