rs587777309

Variant names:

• chr5-161895726-A-C
• rs587777309
• NM_001127644.2:c.917A>C

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3_Moderate PP5

The NM_001127644.2(GABRA1):​c.917A>C​(p.Lys306Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K306N) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: GABRA1 NM_001127644.2 missense
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.21
• Publications: 7 publications found

Genes affected

GABRA1 (HGNC:4075): (gamma-aminobutyric acid type A receptor subunit alpha1) This gene encodes a gamma-aminobutyric acid (GABA) receptor. 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. GABA-A receptors are pentameric, consisting of proteins from several subunit classes: alpha, beta, gamma, delta and rho. Mutations in this gene cause juvenile myoclonic epilepsy and childhood absence epilepsy type 4. Multiple transcript variants encoding the same protein have been identified for this gene. [provided by RefSeq, Jul 2008]

GABRA1 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 19

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• epilepsy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• epilepsy, idiopathic generalized, susceptibility to, 13

  Inheritance: AD Classification: STRONG Submitted by: G2P
• Dravet syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• juvenile myoclonic epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_001127644.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr5-161895727-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 4071944.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.924
• PP5: Variant 5-161895726-A-C is Pathogenic according to our data. Variant chr5-161895726-A-C is described in ClinVar as Pathogenic. ClinVar VariationId is 127075.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001127644.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GABRA1	NM_001127644.2	MANE Select	c.917A>C	p.Lys306Thr	missense	Exon 9 of 10	NP_001121116.1	P14867
	GABRA1	NM_000806.5		c.917A>C	p.Lys306Thr	missense	Exon 10 of 11	NP_000797.2	A8K177
	GABRA1	NM_001127643.2		c.917A>C	p.Lys306Thr	missense	Exon 10 of 11	NP_001121115.1	P14867

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GABRA1	ENST00000393943.10	TSL:1 MANE Select	c.917A>C	p.Lys306Thr	missense	Exon 9 of 10	ENSP00000377517.4	P14867
	GABRA1	ENST00000023897.10	TSL:1	c.917A>C	p.Lys306Thr	missense	Exon 10 of 11	ENSP00000023897.6	P14867
	GABRA1	ENST00000428797.7	TSL:1	c.917A>C	p.Lys306Thr	missense	Exon 10 of 11	ENSP00000393097.2	P14867

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
1	-	-	Developmental and epileptic encephalopathy, 19 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.92	D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Pathogenic	3.5	M
PhyloP100		9.2
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-5.2	D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.99	D
Vest4		0.94
MutPred		0.66		Loss of methylation at K306 (P = 0.004)
MVP		0.95
MPC		3.7
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.91
gMVP		0.98
Mutation Taster		=1/99	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs587777309; hg19: chr5-161322732;