rs1212517874

Variant names:

• chr9-137161053-CA-C
• rs1212517874
• NM_007327.4:c.1198-2delA

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_007327.4(GRIN1):​c.1198-2delA variant causes a splice acceptor, intron change. The variant allele was found at a frequency of 0.00000657 in 152,242 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: GRIN1 NM_007327.4 splice_acceptor, intron
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.73
• Publications: 0 publications found

Genes affected

GRIN1 (HGNC:4584): (glutamate ionotropic receptor NMDA type subunit 1) The protein encoded by this gene is a critical subunit of N-methyl-D-aspartate receptors, members of the glutamate receptor channel superfamily which are heteromeric protein complexes with multiple subunits arranged to form a ligand-gated ion channel. These subunits play a key role in the plasticity of synapses, which is believed to underlie memory and learning. Cell-specific factors are thought to control expression of different isoforms, possibly contributing to the functional diversity of the subunits. Alternatively spliced transcript variants have been described. [provided by RefSeq, Jul 2008]

GRIN1 Gene-Disease associations (from GenCC):

• neurodevelopmental disorder with or without hyperkinetic movements and seizures, autosomal dominant

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• complex neurodevelopmental disorder

  Inheritance: AR, AD Classification: DEFINITIVE Submitted by: ClinGen
• neurodevelopmental disorder with or without hyperkinetic movements and seizures, autosomal recessive

  Inheritance: AR Classification: DEFINITIVE, MODERATE Submitted by: G2P, Ambry Genetics
• developmental and epileptic encephalopathy 101

  Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• autosomal dominant non-syndromic intellectual disability

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

LOC105376328 (HGNC:):

ACMG classification

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

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.050408237 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.3, offset of 18, new splice context is: cgattgtgacgatccaccAGgag. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 9-137161053-CA-C is Pathogenic according to our data. Variant chr9-137161053-CA-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 472571.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN1	NM_007327.4	c.1198-2delA		splice_acceptor_variant, intron_variant	Intron 8 of 19	ENST00000371561.8	NP_015566.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN1	ENST00000371561.8	c.1198-2delA		splice_acceptor_variant, intron_variant	Intron 8 of 19	1	NM_007327.4	ENSP00000360616.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152242 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 32

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152242 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74376

African (AFR) AF: 0.0000241 AC: 1 AN: 41464

American (AMR) AF: 0.00 AC: 0 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10626

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68044

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurodevelopmental disorder with or without hyperkinetic movements and seizures, autosomal dominant Pathogenic:1

Jul 21, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 472571). This variant has not been reported in the literature in individuals affected with GRIN1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.01%). This sequence change affects a splice site in intron 8 of the GRIN1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in GRIN1 are known to be pathogenic (PMID: 27164704, 35393335). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		6.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.72		Position offset: 21
DS_AL_spliceai		1.0		Position offset: 3

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1212517874; hg19: chr9-140055505;