5-162095551-G-C

Variant names:

• chr5-162095551-G-C
• rs796052505
• NM_198904.4:c.316G>C

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP2

The NM_198904.4(GABRG2):​c.316G>C​(p.Ala106Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000187 in 1,600,954 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A106T) has been classified as Pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: GABRG2 NM_198904.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.25

Genes affected

GABRG2 (HGNC:4087): (gamma-aminobutyric acid type A receptor subunit gamma2) This gene encodes a gamma-aminobutyric acid (GABA) receptor. GABA is the major inhibitory neurotransmitter in the mammlian brain, where it acts at GABA-A receptors, which are ligand-gated chloride channels. GABA-A receptors are pentameric, consisting of proteins from several subunit classes: alpha, beta, gamma, delta and rho. Mutations in this gene have been associated with epilepsy and febrile seizures. Multiple transcript variants encoding different isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a topological_domain Extracellular (size 233) in uniprot entity GBRG2_HUMAN there are 9 pathogenic changes around while only 2 benign (82%) in NM_198904.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr5-162095551-G-A is described in Lovd as [Pathogenic].
• PP2: Missense variant in the GABRG2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 34 curated pathogenic missense variants (we use a threshold of 10). The gene has 21 curated benign missense variants. Gene score misZ: 2.9939 (below the threshold of 3.09). Trascript score misZ: 3.9213 (above the threshold of 3.09). GenCC associations: The gene is linked to epilepsy, Dravet syndrome, undetermined early-onset epileptic encephalopathy, generalized epilepsy with febrile seizures plus, developmental and epileptic encephalopathy, 74, febrile seizures, familial, 8, childhood epilepsy with centrotemporal spikes.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GABRG2	NM_198904.4	c.316G>C	p.Ala106Pro	missense_variant	Exon 3 of 10	ENST00000639213.2	NP_944494.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GABRG2	ENST00000639213.2	c.316G>C	p.Ala106Pro	missense_variant	Exon 3 of 10	1	NM_198904.4	ENSP00000491909.2

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152026 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

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

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1448928 Hom.: 0 Cov.: 27 AF XY: 0.00 AC XY: 0 AN XY: 721676

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000182

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152026 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74242

Gnomad4 AFR AF: 0.00

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: 0.000224 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.38
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Benign	0.30	.;.;.;.;.;.;T;.;.;.;.;.;.;.
Eigen	Benign	-0.14
Eigen_PC	Benign	0.14
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Benign	0.79	T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP	Benign	0.049	D
MetaRNN	Uncertain	0.44	T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.82	T
MutationAssessor	Benign	-1.3	.;.;.;.;N;.;N;.;.;.;.;N;.;.
PrimateAI	Pathogenic	0.87	D
PROVEAN	Benign	0.67	.;.;.;.;.;.;.;.;.;.;.;N;N;.
REVEL	Uncertain	0.35
Sift	Benign	0.33	.;.;.;.;.;.;.;.;.;.;.;T;T;.
Sift4G	Benign	0.32	.;.;.;.;.;.;.;.;.;.;.;T;T;.
Polyphen		0.0040, 0.0050	.;.;.;.;B;.;B;.;.;.;.;.;.;.
Vest4		0.29, 0.26
MutPred		0.50		.;.;.;.;Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);.;Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);Loss of sheet (P = 0.1158);
MVP		0.68
MPC		1.9
ClinPred		0.92	D
GERP RS		6.1
Varity_R		0.60
gMVP		0.88

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: rs796052505; hg19: chr5-161522557;