1-2019489-C-G

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Moderate BP6_Moderate BP7

The NM_000815.5(GABRD):c.66C>G(p.Thr22=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★).

• Frequency: Genomes: not found (cov: 27)
• Consequence: GABRD NM_000815.5 splice_region, synonymous
• Scores: Splicing: ADA: 0.002653
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.694

Genes affected

GABRD (HGNC:4084): (gamma-aminobutyric acid type A receptor subunit delta) Gamma-aminobutyric acid (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. The GABA-A receptor is generally pentameric and there are five types of subunits: alpha, beta, gamma, delta, and rho. This gene encodes the delta subunit. Mutations in this gene have been associated with susceptibility to generalized epilepsy with febrile seizures, type 5. Alternatively spliced transcript variants have been described for this gene, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.43).
• BP6: Variant 1-2019489-C-G is Benign according to our data. Variant chr1-2019489-C-G is described in ClinVar as [Likely_benign]. Clinvar id is 2974456.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.694 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GABRD	NM_000815.5	c.66C>G	p.Thr22=	splice_region_variant, synonymous_variant	1/9	ENST00000378585.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GABRD	ENST00000378585.7	c.66C>G	p.Thr22=	splice_region_variant, synonymous_variant	1/9	1	NM_000815.5	P1

Frequencies

GnomAD3 genomes Cov.: 27

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 27

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Idiopathic generalized epilepsy Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2023

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.43
Cadd	Benign	17
Dann	Benign	0.88

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.0027
dbscSNV1_RF	Benign	0.066
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: rs1658715570; hg19: chr1-1950928;