4-46065536-A-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_173536.4(GABRG1):c.370T>G(p.Leu124Val) variant causes a missense change involving the alteration of a non-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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L124F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: GABRG1 NM_173536.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.16

Genes affected

GABRG1 (HGNC:4086): (gamma-aminobutyric acid type A receptor subunit gamma1) The protein encoded by this gene belongs to the ligand-gated ionic channel family. It is an integral membrane protein and plays an important role in inhibiting neurotransmission by binding to the benzodiazepine receptor and opening an integral chloride channel. This gene is clustered with three other family members on chromosome 4. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRG1	NM_173536.4	c.370T>G	p.Leu124Val	missense_variant	4/9	ENST00000295452.5
GABRG1	XM_017007990.2	c.-18T>G		5_prime_UTR_variant	2/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRG1	ENST00000295452.5	c.370T>G	p.Leu124Val	missense_variant	4/9	1	NM_173536.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0;AS_VQSR AF: 0.00 AC: 0 AN: 1450486 Hom.: 0 Cov.: 28 AF XY: 0.00 AC XY: 0 AN XY: 722298

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 03, 2021

The c.370T>G (p.L124V) alteration is located in exon 4 (coding exon 4) of the GABRG1 gene. This alteration results from a T to G substitution at nucleotide position 370, causing the leucine (L) at amino acid position 124 to be replaced by a valine (V). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.68	D
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.35
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.41	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Uncertain	0.66	D
MutationAssessor	Pathogenic	3.8	H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-2.6	D
REVEL	Pathogenic	0.81
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.94
MutPred		0.92		Gain of methylation at K125 (P = 0.0421);
MVP		0.92
MPC		0.60
ClinPred		1.0	D
GERP RS		1.2
Varity_R		0.62
gMVP		0.66

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: chr4-46067553;