rs146381127

Variant names:

• chr1-2029672-C-A
• rs146381127
• NM_000815.5:c.969C>A

Your query was ambiguous. Multiple possible variants found:

• chr1-2029672-C-A
• chr1-2029672-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000815.5(GABRD):​c.969C>A​(p.Ala323Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,234 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. A323A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: GABRD NM_000815.5 synonymous
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.48

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

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
GABRD	NM_000815.5	c.969C>A	p.Ala323Ala	synonymous_variant	Exon 8 of 9	ENST00000378585.7	NP_000806.2
GABRD	XM_017000936.2	c.1674C>A	p.Ala558Ala	synonymous_variant	Exon 7 of 8		XP_016856425.1
GABRD	XM_011541194.4	c.1008C>A	p.Ala336Ala	synonymous_variant	Exon 8 of 9		XP_011539496.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
GABRD	ENST00000378585.7	c.969C>A	p.Ala323Ala	synonymous_variant	Exon 8 of 9	1	NM_000815.5	ENSP00000367848.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250606 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461234 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726920

Gnomad4 AFR exome AF: 0.00 AC: 0 AN: 33480

Gnomad4 AMR exome AF: 0.0000224 AC: 1 AN: 44722

Gnomad4 ASJ exome AF: 0.00 AC: 0 AN: 26136

Gnomad4 EAS exome AF: 0.00 AC: 0 AN: 39698

Gnomad4 SAS exome AF: 0.00 AC: 0 AN: 86258

Gnomad4 FIN exome AF: 0.00 AC: 0 AN: 52798

Gnomad4 NFE exome AF: 0.00 AC: 0 AN: 1111990

Gnomad4 Remaining exome AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Idiopathic generalized epilepsy Uncertain:1

Jul 14, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. ClinVar contains an entry for this variant (Variation ID: 460018). This variant has not been reported in the literature in individuals affected with GABRD-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.003%). This sequence change affects codon 323 of the GABRD mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the GABRD protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	16
DANN	Benign	0.50
FATHMM_MKL	Benign	0.064	N
LIST_S2	Benign	0.23	T
MetaRNN	Benign	0.10	T
GERP RS		-7.0
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.81		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.81		Position offset: 2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs146381127; hg19: chr1-1961111;