Genetic Variant GABRA2:p.Val449Ile (chr4-46250319-C-T) – ACMG Classification: Likely_benign (-6 pts)

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_000807.4(GABRA2):c.1345G>A(p.Val449Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000311 in 1,609,884 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

GABRA2
NM_000807.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.72

Variant links:

Genes affected

GABRA2 (HGNC:4076): (gamma-aminobutyric acid type A receptor subunit alpha2) GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA-A receptors, which are ligand-gated chloride channels. Chloride conductance of these channels can be modulated by agents such as benzodiazepines that bind to the GABA-A receptor. At least 16 distinct subunits of GABA-A receptors have been identified. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2013]

GABRA2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.08857837).

BS2

High AC in GnomAdExome4 at 48 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GABRA2	NM_000807.4 link	c.1345G>A	p.Val449Ile	missense_variant	Exon 10 of 10	ENST00000381620.9	NP_000798.2	P47869-1A0A024R9X6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GABRA2	ENST00000381620.9 link	c.1345G>A	p.Val449Ile	missense_variant	Exon 10 of 10	1	NM_000807.4	ENSP00000371033.4		P47869-1

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151584

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:

0.0000295

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.0000329

AC:

AN:

1458300

Hom.:

Cov.:

AF XY:

0.0000372

AC XY:

AN XY:

725524

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000414

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151584

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

73994

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:

0.0000295

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.00000756

EpiCase

AF:

0.0000546

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

May 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 509 of the GABRA2 protein (p.Val509Ile). This variant is present in population databases (no rsID available, gnomAD 0.0008%). This variant has not been reported in the literature in individuals affected with GABRA2-related conditions. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.069

BayesDel_addAF

Benign

-0.13

BayesDel_noAF

Benign

-0.43

CADD

Benign

DANN

Benign

0.87

DEOGEN2

Benign

0.11

T;T;T;T;T;T

Eigen

Benign

-0.28

Eigen_PC

Benign

-0.059

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.90

.;.;.;D;D;D

M_CAP

Benign

0.018

MetaRNN

Benign

0.089

T;T;T;T;T;T

MetaSVM

Benign

-0.91

MutationAssessor

Benign

0.69

N;N;N;N;.;.

PrimateAI

Uncertain

0.53

PROVEAN

Benign

-0.22

N;N;N;N;.;N

REVEL

Benign

0.17

Sift

Benign

0.19

T;T;T;T;.;T

Sift4G

Benign

0.68

T;T;T;T;T;T

Polyphen

0.012

B;B;B;B;.;.

Vest4

0.056

MVP

0.46

MPC

0.20

ClinPred

0.64

GERP RS

4.9

Varity_R

0.063

gMVP

0.12

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