rs1273394

Variant names:

• chr16-8719430-G-T
• rs1273394
• NM_020686.6:c.-41-16269G>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Strong BA1

The NM_020686.6(ABAT):​c.-41-16269G>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.333 in 151,980 control chromosomes in the GnomAD database, including 8,742 homozygotes. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.33 (8742 hom., cov: 32)
• Consequence: ABAT NM_020686.6 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.400
• Publications: 7 publications found

Genes affected

ABAT (HGNC:23): (4-aminobutyrate aminotransferase) 4-aminobutyrate aminotransferase (ABAT) is responsible for catabolism of gamma-aminobutyric acid (GABA), an important, mostly inhibitory neurotransmitter in the central nervous system, into succinic semialdehyde. The active enzyme is a homodimer of 50-kD subunits complexed to pyridoxal-5-phosphate. The protein sequence is over 95% similar to the pig protein. GABA is estimated to be present in nearly one-third of human synapses. ABAT in liver and brain is controlled by 2 codominant alleles with a frequency in a Caucasian population of 0.56 and 0.44. The ABAT deficiency phenotype includes psychomotor retardation, hypotonia, hyperreflexia, lethargy, refractory seizures, and EEG abnormalities. Multiple alternatively spliced transcript variants encoding the same protein isoform have been found for this gene. [provided by RefSeq, Jul 2008]

ABAT Gene-Disease associations (from GenCC):

• GABA aminotransaminase deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia, Orphanet, G2P
• genetic developmental and epileptic encephalopathy

  Inheritance: AR Classification: MODERATE Submitted by: ClinGen

ACMG classification

Our verdict: Benign. The variant received -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-1.0).
• BA1: GnomAd4 highest subpopulation (AFR) allele frequency at 95% confidence interval = 0.402 is higher than 0.05.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020686.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABAT	NM_020686.6	MANE Select	c.-41-16269G>T		intron	N/A	NP_065737.2
	ABAT	NM_001386615.1		c.-41-16269G>T		intron	N/A	NP_001373544.1
	ABAT	NM_000663.5		c.-42+5565G>T		intron	N/A	NP_000654.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ABAT	ENST00000268251.13	TSL:1 MANE Select	c.-41-16269G>T		intron	N/A	ENSP00000268251.8
	ABAT	ENST00000566590.5	TSL:1	n.-42+5565G>T		intron	N/A	ENSP00000455198.1
	ABAT	ENST00000567812.5	TSL:2	c.4+5551G>T		intron	N/A	ENSP00000456330.1

Frequencies

GnomAD3 genomes AF: 0.333 AC: 50526 AN: 151862 Hom.: 8724 Cov.: 32

Gnomad AFR AF: 0.407

Gnomad AMI AF: 0.308

Gnomad AMR AF: 0.330

Gnomad ASJ AF: 0.329

Gnomad EAS AF: 0.122

Gnomad SAS AF: 0.237

Gnomad FIN AF: 0.371

Gnomad MID AF: 0.377

Gnomad NFE AF: 0.306

Gnomad OTH AF: 0.323

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.333 AC: 50571 AN: 151980 Hom.: 8742 Cov.: 32 AF XY: 0.334 AC XY: 24777 AN XY: 74276

African (AFR) AF: 0.407 AC: 16872 AN: 41410

American (AMR) AF: 0.330 AC: 5036 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.329 AC: 1141 AN: 3468

East Asian (EAS) AF: 0.122 AC: 633 AN: 5176

South Asian (SAS) AF: 0.236 AC: 1134 AN: 4812

European-Finnish (FIN) AF: 0.371 AC: 3907 AN: 10544

Middle Eastern (MID) AF: 0.378 AC: 111 AN: 294

European-Non Finnish (NFE) AF: 0.306 AC: 20783 AN: 67972

Other (OTH) AF: 0.319 AC: 674 AN: 2112

Alfa AF: 0.317 Hom.: 13442

Bravo AF: 0.335

Asia WGS AF: 0.172 AC: 604 AN: 3478

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-1.0
CADD	Benign	1.2
DANN	Benign	0.37
PhyloP100		0.40
Mutation Taster		=100/0	polymorphism (auto)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1273394; hg19: chr16-8813287;