4-46250331-G-A

Position:

• chr4-46250331-G-A

Variant summary

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

The NM_000807.4(GABRA2):​c.1333C>T​(p.Pro445Ser) 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. 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. P445H) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GABRA2 NM_000807.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.67

Genes affected

GABRA2 (HGNC:4076): (gamma-aminobutyric acid type A receptor subunit alpha2) 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. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2013]

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), GABRA2. . Gene score misZ 3.1277 (greater than the threshold 3.09). Trascript score misZ 3.4041 (greater than threshold 3.09). GenCC has associacion of gene with developmental and epileptic encephalopathy, 78, undetermined early-onset epileptic encephalopathy.
• BP4: Computational evidence support a benign effect (MetaRNN=0.1944904).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRA2	NM_000807.4	c.1333C>T	p.Pro445Ser	missense_variant	10/10	ENST00000381620.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRA2	ENST00000381620.9	c.1333C>T	p.Pro445Ser	missense_variant	10/10	1	NM_000807.4	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jan 26, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Benign	0.13	T;T;T;T;T;T
Eigen	Benign	0.0097
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.91	.;.;.;D;D;D
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.19	T;T;T;T;T;T
MetaSVM	Benign	-0.49	T
MutationAssessor	Benign	1.2	L;L;L;L;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-1.2	N;N;N;N;.;N
REVEL	Uncertain	0.35
Sift	Benign	0.24	T;T;T;T;.;T
Sift4G	Benign	0.40	T;T;T;T;T;T
Polyphen		0.10	B;B;B;B;.;.
Vest4		0.43
MutPred		0.31		Loss of glycosylation at S450 (P = 0.0244);Loss of glycosylation at S450 (P = 0.0244);Loss of glycosylation at S450 (P = 0.0244);Loss of glycosylation at S450 (P = 0.0244);.;.;
MVP		0.64
MPC		0.33
ClinPred		0.73	D
GERP RS		5.8
Varity_R		0.17
gMVP		0.55

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: chr4-46252348;