dbSNP rs1554101092: GABRG2:p.Met380Ile (chr5-162151741-G-A) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_198904.4(GABRG2):c.1140G>A(p.Met380Ile) variant causes a missense change. The variant allele was found at a frequency of 0.000000686 in 1,458,298 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

GABRG2
NM_198904.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.52

Publications

0 publications found

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 Gene-Disease associations (from GenCC):

epilepsy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
developmental and epileptic encephalopathy, 74
Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
febrile seizures, familial, 8
Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
Dravet syndrome
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
generalized epilepsy with febrile seizures plus
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
self-limited epilepsy with centrotemporal spikes
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
undetermined early-onset epileptic encephalopathy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

GABRG2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GABRG2	NM_198904.4 link	c.1140G>A	p.Met380Ile	missense_variant	Exon 9 of 10	ENST00000639213.2	NP_944494.1	P18507-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GABRG2	ENST00000639213.2 link	c.1140G>A	p.Met380Ile	missense_variant	Exon 9 of 10	1	NM_198904.4	ENSP00000491909.2		P18507-2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.86e-7

AC:

AN:

1458298

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

725426

show subpopulations

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

African (AFR)

AF:

0.00

AC:

AN:

33328

American (AMR)

AF:

0.00

AC:

AN:

44562

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26048

East Asian (EAS)

AF:

0.00

AC:

AN:

39432

South Asian (SAS)

AF:

0.00

AC:

AN:

85636

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53158

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5748

European-Non Finnish (NFE)

AF:

9.01e-7

AC:

AN:

1110152

Other (OTH)

AF:

0.00

AC:

AN:

60234

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.275

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

Cov.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Apr 28, 2017

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Lines of evidence used in support of classification: UNCERTAIN: Alteration(s) of Uncertain Clinical Significance Detected -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.19

BayesDel_addAF

Uncertain

0.068

BayesDel_noAF

Benign

-0.14

CADD

Benign

(source)

DANN

Benign

0.96

Eigen

Benign

-0.013

Eigen_PC

Uncertain

0.24

FATHMM_MKL

Uncertain

0.95

LIST_S2

Benign

0.80

T;T;T;T;T;T

M_CAP

Benign

0.047

MetaRNN

Uncertain

0.42

T;T;T;T;T;T

MetaSVM

Benign

-0.99

PhyloP100

6.5

PrimateAI

Pathogenic

0.82

PROVEAN

Benign

-0.48

.;.;.;.;.;N

REVEL

Uncertain

0.33

Sift

Benign

0.21

.;.;.;.;.;T

Sift4G

Benign

0.28

.;.;.;.;.;T

Polyphen

0.0

.;B;.;.;.;.

Vest4

0.63

MutPred

0.52

.;Loss of disorder (P = 0.065);.;Loss of disorder (P = 0.065);.;.;

MVP

0.85

MPC

0.56

ClinPred

0.99

GERP RS

5.8

gMVP

0.52

Mutation Taster

=68/32

polymorphism

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.060

Details are displayed if max score is > 0.2

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

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over