9-98454172-C-T

Position:

chr9-98454172-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2BS2

The NM_005458.8(GABBR2):c.1045G>A(p.Val349Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,974 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

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

Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

GABBR2
NM_005458.8 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.91

Variant links:

Genes affected

GABBR2 (HGNC:4507): (gamma-aminobutyric acid type B receptor subunit 2) The multi-pass membrane protein encoded by this gene belongs to the G-protein coupled receptor 3 family and GABA-B receptor subfamily. The GABA-B receptors inhibit neuronal activity through G protein-coupled second-messenger systems, which regulate the release of neurotransmitters, and the activity of ion channels and adenylyl cyclase. This receptor subunit forms an active heterodimeric complex with GABA-B receptor subunit 1, neither of which is effective on its own. Allelic variants of this gene have been associated with nicotine dependence.[provided by RefSeq, Jan 2010]

GABBR2 links:

GABBR2 (HGNC:):

GABBR2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), GABBR2. . Gene score misZ 4.6253 (greater than the threshold 3.09). Trascript score misZ 4.0975 (greater than threshold 3.09). GenCC has associacion of gene with developmental and epileptic encephalopathy, 59, neurodevelopmental disorder with poor language and loss of hand skills, atypical Rett syndrome.

BS2

High AC in GnomAdExome4 at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GABBR2	NM_005458.8 linkuse as main transcript	c.1045G>A	p.Val349Met	missense_variant	7/19	ENST00000259455.4	NP_005449.5	O75899H9NIL8
GABBR2	XM_017015331.3 linkuse as main transcript	c.751G>A	p.Val251Met	missense_variant	6/18		XP_016870820.1
GABBR2	XM_005252316.6 linkuse as main transcript	c.271G>A	p.Val91Met	missense_variant	5/17		XP_005252373.1
GABBR2	XM_017015332.3 linkuse as main transcript	c.271G>A	p.Val91Met	missense_variant	4/16		XP_016870821.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
GABBR2	ENST00000259455.4 linkuse as main transcript	c.1045G>A	p.Val349Met	missense_variant	7/19	1	NM_005458.8	ENSP00000259455.2	O75899
GABBR2	ENST00000634919.1 linkuse as main transcript	n.823G>A		non_coding_transcript_exon_variant	6/6	5
GABBR2	ENST00000637410.1 linkuse as main transcript	n.823G>A		non_coding_transcript_exon_variant	7/19	5

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152162

Hom.:

Cov.:

show subpopulations

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

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251424

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135892

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000616

AC:

AN:

1461812

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727206

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:

0.00000630

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152162

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74336

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000340

ExAC

AF:

0.0000165

AC:

Asia WGS

AF:

0.000577

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Epileptic encephalopathy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 06, 2023

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 349 of the GABBR2 protein (p.Val349Met). This variant is present in population databases (rs759044661, gnomAD 0.007%). This missense change has been observed in individuals with clinical features of early onset epileptic encephalopathy (PMID: 34055682; Invitae). ClinVar contains an entry for this variant (Variation ID: 575804). 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) performed at Invitae indicates that this missense variant is not expected to disrupt GABBR2 protein function with a negative predictive value of 80%. 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

0.10

BayesDel_addAF

Uncertain

0.046

BayesDel_noAF

Uncertain

0.010

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.12

Eigen

Uncertain

0.67

Eigen_PC

Pathogenic

0.73

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.84

M_CAP

Benign

0.043

MetaRNN

Uncertain

0.49

MetaSVM

Uncertain

0.12

MutationAssessor

Benign

1.2

PrimateAI

Uncertain

0.61

PROVEAN

Benign

-0.34

REVEL

Uncertain

0.54

Sift

Benign

0.12

Sift4G

Benign

0.25

Polyphen

1.0

Vest4

0.42

MutPred

0.52

Loss of ubiquitination at K353 (P = 0.1264);

MVP

0.83

MPC

1.8

ClinPred

0.65

GERP RS

5.8

Varity_R

0.35

gMVP

0.62

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