rs587780341

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP2

The NM_198904.4(GABRG2):c.1334G>A(p.Arg445His) variant causes a missense change. The variant allele was found at a frequency of 0.00000372 in 1,613,858 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R445L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

GABRG2
NM_198904.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.73

Variant links:

Genes affected

GABRG2 (HGNC:4087): (gamma-aminobutyric acid type A receptor subunit gamma2) This gene encodes a gamma-aminobutyric acid (GABA) receptor. GABA is the major inhibitory neurotransmitter in the mammlian brain, where it acts at GABA-A receptors, which are ligand-gated chloride channels. GABA-A receptors are pentameric, consisting of proteins from several subunit classes: alpha, beta, gamma, delta and rho. Mutations in this gene have been associated with epilepsy and febrile seizures. Multiple transcript variants encoding different isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]

GABRG2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PP2

Missense variant where missense usually causes diseases, GABRG2

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRG2	NM_198904.4 linkuse as main transcript	c.1334G>A	p.Arg445His	missense_variant	10/10	ENST00000639213.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRG2	ENST00000639213.2 linkuse as main transcript	c.1334G>A	p.Arg445His	missense_variant	10/10	1	NM_198904.4	A1	P18507-2

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152062

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000796

AC:

AN:

251122

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135720

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.00000881

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000342

AC:

AN:

1461796

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727204

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152062

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74270

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

GABRG2-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Apr 19, 2023

The GABRG2 c.1310G>A variant is predicted to result in the amino acid substitution p.Arg437His. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0040% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/5-161580280-G-A). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 26, 2022

The c.1310G>A (p.R437H) alteration is located in exon 9 (coding exon 9) of the GABRG2 gene. This alteration results from a G to A substitution at nucleotide position 1310, causing the arginine (R) at amino acid position 437 to be replaced by a histidine (H). 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

Mayo Clinic Laboratories, Mayo Clinic

Aug 26, 2019

- -

Epilepsy, childhood absence 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Epilepsy, childhood absence 2;C1969810:Febrile seizures, familial, 8

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 10, 2023

This variant is present in population databases (no rsID available, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with GABRG2-related conditions. ClinVar contains an entry for this variant (Variation ID: 352643). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on GABRG2 protein function. This variant disrupts the p.Arg437 amino acid residue in GABRG2. Other variant(s) that disrupt this residue have been determined to be pathogenic (Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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. This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 437 of the GABRG2 protein (p.Arg437His). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.14

BayesDel_addAF

Uncertain

0.028

BayesDel_noAF

Uncertain

-0.020

Cadd

Uncertain

Dann

Uncertain

0.98

Eigen

Benign

0.0077

Eigen_PC

Uncertain

0.26

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.91

D;D;D;D;D;D;D;D;D;D;D

M_CAP

Benign

0.057

MetaRNN

Uncertain

0.52

D;D;D;D;D;D;D;D;D;D;D

MetaSVM

Benign

-0.61

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Pathogenic

0.90

Polyphen

0.0030, 0.0020

.;.;.;B;.;B;.;.;.;.;.

Vest4

0.21

MutPred

0.61

.;.;.;.;.;Loss of MoRF binding (P = 0.0083);.;.;.;.;.;

MVP

0.78

MPC

1.6

ClinPred

0.36

GERP RS

6.0

Varity_R

0.19

gMVP

0.84

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