4-46051482-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_173536.4(GABRG1):c.1073C>T(p.Thr358Ile) 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 (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: GABRG1 NM_173536.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.90

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.759

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRG1	NM_173536.4	c.1073C>T	p.Thr358Ile	missense_variant	8/9	ENST00000295452.5
GABRG1	XM_017007990.2	c.686C>T	p.Thr229Ile	missense_variant	6/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRG1	ENST00000295452.5	c.1073C>T	p.Thr358Ile	missense_variant	8/9	1	NM_173536.4	P1

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 specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 10, 2023

The c.1073C>T (p.T358I) alteration is located in exon 8 (coding exon 8) of the GABRG1 gene. This alteration results from a C to T substitution at nucleotide position 1073, causing the threonine (T) at amino acid position 358 to be replaced by an isoleucine (I). 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	Benign	0.23
BayesDel_addAF	Uncertain	0.042	T
BayesDel_noAF	Benign	-0.18
Cadd	Uncertain	23
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.56	D
Eigen	Uncertain	0.25
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.90	D
M_CAP	Benign	0.071	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Uncertain	0.065	D
MutationAssessor	Benign	1.3	L
MutationTaster	Benign	0.92	D
PrimateAI	Uncertain	0.61	T
PROVEAN	Uncertain	-2.6	D
REVEL	Uncertain	0.46
Sift	Benign	0.058	T
Sift4G	Uncertain	0.044	D
Polyphen		0.57	P
Vest4		0.74
MutPred		0.56		Loss of loop (P = 0.0203);
MVP		0.93
MPC		0.57
ClinPred		0.98	D
GERP RS		4.8
Varity_R		0.23
gMVP		0.79

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: chr4-46053499;