rs1555401442

Positions:

• chr15-26561171-T-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PP2 PP3_Strong PP5

The NM_000814.6(GABRB3):​c.841A>G​(p.Thr281Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: GABRB3 NM_000814.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2
• Conservation: PhyloP100: 7.90

Genes affected

GABRB3 (HGNC:4083): (gamma-aminobutyric acid type A receptor subunit beta3) This gene encodes a member of the ligand-gated ionic channel family. The encoded protein is one the subunits of a multi-subunit chloride channel that serves as the receptor for gamma-aminobutyric acid, a major inhibitory neurotransmitter of the mammalian nervous system. This gene is located on the long arm of chromosome 15 in a cluster with two other genes encoding related subunits of the family. This gene may be associated with the pathogenesis of several disorders including Angelman syndrome, Prader-Willi syndrome, nonsyndromic orofacial clefts, epilepsy and autism. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jul 2013]

GABRB3 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), GABRB3. . Gene score misZ 3.3856 (greater than the threshold 3.09). Trascript score misZ 4.4544 (greater than threshold 3.09). GenCC has associacion of gene with childhood absence epilepsy, developmental and epileptic encephalopathy, 43, developmental and epileptic encephalopathy, Lennox-Gastaut syndrome, epilepsy, childhood absence, susceptibility to, 5.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.955
• PP5: Variant 15-26561171-T-C is Pathogenic according to our data. Variant chr15-26561171-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 548619.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=2, Likely_pathogenic=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GABRB3	NM_000814.6	c.841A>G	p.Thr281Ala	missense_variant	8/9	ENST00000311550.10	NP_000805.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GABRB3	ENST00000311550.10	c.841A>G	p.Thr281Ala	missense_variant	8/9	1	NM_000814.6	ENSP00000308725.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Developmental and epileptic encephalopathy, 43 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Mar 02, 2023

- -

Developmental and epileptic encephalopathy, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genomic Research Center, Shahid Beheshti University of Medical Sciences

Mar 05, 2018

- -

Epilepsy, childhood absence, susceptibility to, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genomic Research Center, Shahid Beheshti University of Medical Sciences

Mar 05, 2018

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.87	.;D;.;.;.;.;.;.;.
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.97	.;D;D;D;D;.;D;D;.
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Pathogenic	4.5	.;H;.;.;H;.;.;.;.
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-4.9	.;D;.;D;D;.;.;D;D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0010	.;D;.;D;D;.;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;.;.;D;D
Polyphen		1.0	.;D;.;D;D;.;.;.;.
Vest4		0.93
MutPred		0.78		.;.;.;Loss of glycosylation at T337 (P = 0.0191);.;.;.;.;.;
MVP		0.98
MPC		2.2
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.88
gMVP		0.97

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

Other links and lift over

dbSNP: rs1555401442; hg19: chr15-26806318;