9-98306256-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_005458.8(GABBR2):​c.2094C>A​(p.Asn698Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,214 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N698S) has been classified as Likely benign.

Frequency

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

Consequence

GABBR2
NM_005458.8 missense

Scores

7
8
3

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: -0.126

Publications

2 publications found
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 Gene-Disease associations (from GenCC):
  • developmental and epileptic encephalopathy, 59
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • neurodevelopmental disorder with poor language and loss of hand skills
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • atypical Rett syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 4 uncertain in NM_005458.8
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.947

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005458.8. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GABBR2
NM_005458.8
MANE Select
c.2094C>Ap.Asn698Lys
missense
Exon 15 of 19NP_005449.5

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GABBR2
ENST00000259455.4
TSL:1 MANE Select
c.2094C>Ap.Asn698Lys
missense
Exon 15 of 19ENSP00000259455.2
GABBR2
ENST00000634457.1
TSL:5
c.321C>Ap.Asn107Lys
missense
Exon 3 of 4ENSP00000489352.1
GABBR2
ENST00000634354.1
TSL:5
n.316C>A
non_coding_transcript_exon
Exon 1 of 2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152214
Hom.:
0
Cov.:
32
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
GnomAD4 exome
Cov.:
32
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152214
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5200
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68046
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Uncertain
0.064
T
BayesDel_noAF
Benign
-0.15
CADD
Benign
20
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.87
D
Eigen
Benign
0.13
Eigen_PC
Benign
-0.052
FATHMM_MKL
Uncertain
0.82
D
LIST_S2
Uncertain
0.92
D
M_CAP
Pathogenic
0.51
D
MetaRNN
Pathogenic
0.95
D
MetaSVM
Uncertain
0.59
D
MutationAssessor
Uncertain
2.4
M
PhyloP100
-0.13
PrimateAI
Pathogenic
0.91
D
PROVEAN
Pathogenic
-5.6
D
REVEL
Pathogenic
0.75
Sift
Uncertain
0.0020
D
Sift4G
Uncertain
0.016
D
Polyphen
1.0
D
Vest4
0.92
MutPred
0.89
Gain of methylation at N698 (P = 0.0197)
MVP
0.88
MPC
1.6
ClinPred
1.0
D
GERP RS
-1.3
Varity_R
0.96
gMVP
1.0
Mutation Taster
=36/64
disease causing

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

Other links and lift over

dbSNP: rs763391651; hg19: chr9-101068538; API