chr16-8781379-C-G

Variant names:

• chr16-8781379-C-G
• rs61730647
• NM_020686.6:c.1452C>G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_020686.6(ABAT):​c.1452C>G​(p.His484Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,202 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 32)
• Consequence: ABAT NM_020686.6 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -3.06

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]

TMEM186 (HGNC:24530): (transmembrane protein 186) This gene encodes a potential transmembrane protein. [provided by RefSeq, Dec 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.94

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ABAT	NM_020686.6	c.1452C>G	p.His484Gln	missense_variant	Exon 16 of 16	ENST00000268251.13	NP_065737.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ABAT	ENST00000268251.13	c.1452C>G	p.His484Gln	missense_variant	Exon 16 of 16	1	NM_020686.6	ENSP00000268251.8

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152202 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000385

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 34

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152202 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74352

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000385

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.79
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	-0.010
CADD	Benign	5.4
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.62	D;D;.;D
Eigen	Benign	-0.44
Eigen_PC	Benign	-0.63
FATHMM_MKL	Benign	0.21	N
LIST_S2	Uncertain	0.87	.;D;D;.
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.94	D;D;D;D
MetaSVM	Benign	-0.76	T
MutationAssessor	Pathogenic	3.4	M;M;.;M
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-7.8	D;D;D;D
REVEL	Uncertain	0.50
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	D;D;.;D
Vest4		0.77
MutPred		0.84		Gain of relative solvent accessibility (P = 0.1259);Gain of relative solvent accessibility (P = 0.1259);.;Gain of relative solvent accessibility (P = 0.1259);
MVP		0.21
MPC		1.0
ClinPred		1.0	D
GERP RS		-6.1
Varity_R		0.92
gMVP		0.80

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

Publications

LitVar

Other links and lift over

dbSNP: rs61730647; hg19: chr16-8875236;