1-2025531-C-T

Position:

chr1-2025531-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000815.5(GABRD):c.263C>T(p.Thr88Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000105 in 1,612,844 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

GABRD
NM_000815.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.75

Variant links:

Genes affected

GABRD (HGNC:4084): (gamma-aminobutyric acid type A receptor subunit delta) Gamma-aminobutyric acid (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. The GABA-A receptor is generally pentameric and there are five types of subunits: alpha, beta, gamma, delta, and rho. This gene encodes the delta subunit. Mutations in this gene have been associated with susceptibility to generalized epilepsy with febrile seizures, type 5. Alternatively spliced transcript variants have been described for this gene, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]

GABRD links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.941

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
GABRD	NM_000815.5 linkuse as main transcript	c.263C>T	p.Thr88Met	missense_variant	4/9	ENST00000378585.7	NP_000806.2
GABRD	XM_017000936.2 linkuse as main transcript	c.968C>T	p.Thr323Met	missense_variant	3/8		XP_016856425.1
GABRD	XM_011541194.4 linkuse as main transcript	c.302C>T	p.Thr101Met	missense_variant	4/9		XP_011539496.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GABRD	ENST00000378585.7 linkuse as main transcript	c.263C>T	p.Thr88Met	missense_variant	4/9	1	NM_000815.5	ENSP00000367848	P1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152258

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000319

AC:

AN:

250536

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135736

show subpopulations

Gnomad AFR exome

AF:

0.0000618

Gnomad AMR exome

AF:

0.000174

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1460586

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

726620

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000134

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000232

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000630

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152258

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74390

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000554

Hom.:

Bravo

AF:

0.0000453

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000165

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 21, 2024

The c.263C>T (p.T88M) alteration is located in exon 4 (coding exon 4) of the GABRD gene. This alteration results from a C to T substitution at nucleotide position 263, causing the threonine (T) at amino acid position 88 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Idiopathic generalized epilepsy

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 01, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 460008). This variant has not been reported in the literature in individuals affected with GABRD-related conditions. This variant is present in population databases (rs373508468, gnomAD 0.02%). This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 88 of the GABRD protein (p.Thr88Met). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.72

BayesDel_addAF

Pathogenic

0.17

BayesDel_noAF

Pathogenic

0.28

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.74

D;.;.;.;.

Eigen

Pathogenic

0.71

Eigen_PC

Uncertain

0.66

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Pathogenic

0.99

D;D;D;D;D

M_CAP

Pathogenic

0.32

MetaRNN

Pathogenic

0.94

D;D;D;D;D

MetaSVM

Uncertain

0.35

MutationAssessor

Uncertain

2.3

M;.;.;.;.

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.73

PROVEAN

Pathogenic

-5.3

D;.;.;.;.

REVEL

Pathogenic

0.86

Sift

Pathogenic

0.0

D;.;.;.;.

Sift4G

Pathogenic

0.0

D;.;.;.;.

Polyphen

1.0

D;.;.;.;.

Vest4

0.87

MVP

0.82

MPC

1.9

ClinPred

0.94

GERP RS

4.4

Varity_R

0.85

gMVP

0.72

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

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