rs16966243

Variant names:

• chr16-9755072-A-C
• rs16966243
• NM_001134407.3:c.*8077T>G

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_001134407.3(GRIN2A):​c.*8077T>G variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.01 in 199,214 control chromosomes in the GnomAD database, including 28 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★).

• Frequency:
  • Genomes: 𝑓 0.012 (27 hom., cov: 32)
  • Exomes 𝑓: 0.0024 (1 hom.)
• Consequence: GRIN2A NM_001134407.3 3_prime_UTR
• Clinical Significance: Benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.412
• Publications: 1 publications found

Genes affected

GRIN2A (HGNC:4585): (glutamate ionotropic receptor NMDA type subunit 2A) This gene encodes a member of the glutamate-gated ion channel protein family. The encoded protein is an N-methyl-D-aspartate (NMDA) receptor subunit. NMDA receptors are both ligand-gated and voltage-dependent, and are involved in long-term potentiation, an activity-dependent increase in the efficiency of synaptic transmission thought to underlie certain kinds of memory and learning. These receptors are permeable to calcium ions, and activation results in a calcium influx into post-synaptic cells, which results in the activation of several signaling cascades. Disruption of this gene is associated with focal epilepsy and speech disorder with or without cognitive disability. Alternative splicing results in multiple transcript variants. [provided by RefSeq, May 2014]

GRIN2A Gene-Disease associations (from GenCC):

• complex neurodevelopmental disorder

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• Landau-Kleffner syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• continuous spikes and waves during sleep

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• early-onset epileptic encephalopathy and intellectual disability due to GRIN2A mutation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• rolandic epilepsy-speech dyspraxia syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• self-limited epilepsy with centrotemporal spikes

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• neurodevelopmental disorder

  Inheritance: AR Classification: LIMITED Submitted by: G2P

ACMG classification

Our verdict: Benign. The variant received -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BP6: Variant 16-9755072-A-C is Benign according to our data. Variant chr16-9755072-A-C is described in ClinVar as [Benign]. Clinvar id is 321476.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.0124 (1885/152304) while in subpopulation AFR AF = 0.0425 (1766/41562). AF 95% confidence interval is 0.0408. There are 27 homozygotes in GnomAd4. There are 915 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 27 AD,AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GRIN2A	NM_001134407.3	c.*8077T>G		3_prime_UTR_variant	Exon 13 of 13	ENST00000330684.4	NP_001127879.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GRIN2A	ENST00000330684.4	c.*8077T>G		3_prime_UTR_variant	Exon 13 of 13	1	NM_001134407.3	ENSP00000332549.3
GRIN2A	ENST00000396573.6	c.*8077T>G		3_prime_UTR_variant	Exon 14 of 14	1		ENSP00000379818.2

Frequencies

GnomAD3 genomes AF: 0.0123 AC: 1877 AN: 152186 Hom.: 27 Cov.: 32

Gnomad AFR AF: 0.0424

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00577

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000206

Gnomad OTH AF: 0.00812

GnomAD4 exome AF: 0.00243 AC: 114 AN: 46910 Hom.: 1 Cov.: 0 AF XY: 0.00202 AC XY: 44 AN XY: 21732

African (AFR) AF: 0.0460 AC: 89 AN: 1936

American (AMR) AF: 0.00679 AC: 9 AN: 1326

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 2984

East Asian (EAS) AF: 0.00 AC: 0 AN: 7592

South Asian (SAS) AF: 0.00 AC: 0 AN: 398

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 26

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 288

European-Non Finnish (NFE) AF: 0.0000703 AC: 2 AN: 28432

Other (OTH) AF: 0.00356 AC: 14 AN: 3928

GnomAD4 genome AF: 0.0124 AC: 1885 AN: 152304 Hom.: 27 Cov.: 32 AF XY: 0.0123 AC XY: 915 AN XY: 74484

African (AFR) AF: 0.0425 AC: 1766 AN: 41562

American (AMR) AF: 0.00569 AC: 87 AN: 15284

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5190

South Asian (SAS) AF: 0.000207 AC: 1 AN: 4830

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 292

European-Non Finnish (NFE) AF: 0.000206 AC: 14 AN: 68020

Other (OTH) AF: 0.00803 AC: 17 AN: 2116

Alfa AF: 0.00738 Hom.: 10

Bravo AF: 0.0144

Asia WGS AF: 0.00202 AC: 7 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Landau-Kleffner syndrome Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	2.7
DANN	Benign	0.82
PhyloP100		-0.41

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: rs16966243; hg19: chr16-9848929;