chr5-161689094-C-G

Position:

• chr5-161689094-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The ENST00000274545.10(GABRA6):​c.371C>G​(p.Ser124Cys) 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. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GABRA6 ENST00000274545.10 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.81

Genes affected

GABRA6 (HGNC:4080): (gamma-aminobutyric acid type A receptor subunit alpha6) 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. At least 16 distinct subunits of GABA-A receptors have been identified. [provided by RefSeq, Jul 2008]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.932

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
GABRA6	NM_000811.3	c.371C>G	p.Ser124Cys	missense_variant	4/9	ENST00000274545.10	NP_000802.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
GABRA6	ENST00000274545.10	c.371C>G	p.Ser124Cys	missense_variant	4/9	1	NM_000811.3	ENSP00000274545	P1
	ENST00000521984.1	n.149+166G>C		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Childhood absence epilepsy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 14, 2017

This sequence change replaces serine with cysteine at codon 124 of the GABRA6 protein (p.Ser124Cys). The serine residue is highly conserved and there is a moderate physicochemical difference between serine and cysteine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a GABRA6-related disease. 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, but these predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.63
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.67	D;.;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.92	D;D;D;D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.93	D;D;D;D
MetaSVM	Uncertain	0.69	D
MutationAssessor	Pathogenic	3.4	M;.;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Uncertain	-4.2	D;D;D;D
REVEL	Pathogenic	0.88
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;.;.;.
Vest4		0.82
MutPred		0.78		Loss of disorder (P = 0.0043);.;.;.;
MVP		0.98
MPC		0.41
ClinPred		1.0	D
GERP RS		5.7
Varity_R		0.91
gMVP		0.68

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

Other links and lift over

dbSNP: rs1554115593; hg19: chr5-161116100;