chr5-161294209-C-A

Position:

• chr5-161294209-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_001371727.1(GABRB2):​c.1411G>T​(p.Ala471Ser) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A471T) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GABRB2 NM_001371727.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.70

Genes affected

GABRB2 (HGNC:4082): (gamma-aminobutyric acid type A receptor subunit beta2) The gamma-aminobutyric acid (GABA) A receptor is a multisubunit chloride channel that mediates the fastest inhibitory synaptic transmission in the central nervous system. This gene encodes GABA A receptor, beta 2 subunit. It is mapped to chromosome 5q34 in a cluster comprised of genes encoding alpha 1 and gamma 2 subunits of the GABA A receptor. Alternative splicing of this gene generates 2 transcript variants, differing by a 114 bp insertion. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 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), GABRB2. . Gene score misZ 3.3968 (greater than the threshold 3.09). Trascript score misZ 4.0905 (greater than threshold 3.09). GenCC has associacion of gene with undetermined early-onset epileptic encephalopathy, epileptic encephalopathy, infantile or early childhood, 2.
• BP4: Computational evidence support a benign effect (MetaRNN=0.19087479).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRB2	NM_001371727.1	c.1411G>T	p.Ala471Ser	missense_variant	10/10	ENST00000393959.6
GABRB2	NM_021911.3	c.1411G>T	p.Ala471Ser	missense_variant	11/11
GABRB2	NM_000813.3	c.1297G>T	p.Ala433Ser	missense_variant	10/10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRB2	ENST00000393959.6	c.1411G>T	p.Ala471Ser	missense_variant	10/10	1	NM_001371727.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 30, 2022

This variant has not been reported in the literature in individuals affected with GABRB2-related conditions. 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. 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 GABRB2 protein function. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 471 of the GABRB2 protein (p.Ala471Ser). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.16
BayesDel_addAF	Benign	-0.0043	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Benign	0.26	T;T;.;T;.;T
Eigen	Benign	-0.0072
Eigen_PC	Benign	0.20
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.89	.;D;.;D;D;D
M_CAP	Benign	0.019	T
MetaRNN	Benign	0.19	T;T;T;T;T;T
MetaSVM	Benign	-0.39	T
MutationAssessor	Benign	1.1	L;L;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Pathogenic	0.81	D
PROVEAN	Benign	-0.82	N;N;N;N;N;N
REVEL	Uncertain	0.30
Sift	Benign	0.39	T;T;T;T;T;T
Sift4G	Benign	0.51	T;T;T;T;T;T
Polyphen		0.013	B;B;B;B;B;B
Vest4		0.17
MutPred		0.46		Gain of phosphorylation at A471 (P = 0.006);Gain of phosphorylation at A471 (P = 0.006);.;.;.;.;
MVP		0.63
MPC		0.37
ClinPred		0.45	T
GERP RS		5.7
Varity_R		0.12
gMVP		0.57

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr5-160721216; COSMIC: COSV50910168;