rs764665721

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020686.6(ABAT):c.1307G>A(p.Arg436Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000124 in 1,614,020 control chromosomes in the GnomAD database, with no homozygous occurrence. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

ABAT
NM_020686.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.09

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ABAT	NM_020686.6 linkuse as main transcript	c.1307G>A	p.Arg436Gln	missense_variant	15/16	ENST00000268251.13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ABAT	ENST00000268251.13 linkuse as main transcript	c.1307G>A	p.Arg436Gln	missense_variant	15/16	1	NM_020686.6	P1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152144

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000358

AC:

AN:

251468

Hom.:

AF XY:

0.0000441

AC XY:

AN XY:

135920

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000703

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461876

Hom.:

Cov.:

AF XY:

0.0000165

AC XY:

AN XY:

727236

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000101

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000117

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152144

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74312

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.0000576

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Gamma-aminobutyric acid transaminase deficiency

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

May 29, 2022

This variant has not been reported in the literature in individuals affected with ABAT-related conditions. This variant is present in population databases (rs764665721, gnomAD 0.006%). This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 436 of the ABAT protein (p.Arg436Gln). ClinVar contains an entry for this variant (Variation ID: 582402). 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 missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.088

BayesDel_addAF

Benign

-0.17

BayesDel_noAF

Benign

-0.30

Cadd

Benign

Dann

Uncertain

0.99

DEOGEN2

Benign

0.30

T;T;.;T;T

Eigen

Benign

-0.0032

Eigen_PC

Benign

0.089

FATHMM_MKL

Uncertain

0.92

M_CAP

Benign

0.068

MetaRNN

Uncertain

0.54

D;D;D;D;D

MetaSVM

Uncertain

-0.10

MutationAssessor

Benign

0.75

N;N;.;N;.

MutationTaster

Benign

1.0

D;D;D;D;D

PrimateAI

Benign

0.38

PROVEAN

Benign

-1.7

N;N;N;N;N

REVEL

Uncertain

0.39

Sift

Benign

0.24

T;T;T;T;T

Sift4G

Benign

0.43

T;T;T;T;T

Polyphen

0.55

P;P;.;P;.

Vest4

0.32

MutPred

0.71

Loss of methylation at R436 (P = 0.0015);Loss of methylation at R436 (P = 0.0015);.;Loss of methylation at R436 (P = 0.0015);Loss of methylation at R436 (P = 0.0015);

MVP

0.80

MPC

0.36

ClinPred

0.40

GERP RS

4.3

Varity_R

0.11

gMVP

0.74

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over