rs386833617

chr10-124403821-G-Achr10-124403821-G-Cchr10-124403821-G-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000274.4(OAT):c.748C>T(p.Arg250Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000958 in 1,461,768 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. R250R) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: OAT NM_000274.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 2.04

Genes affected

OAT (HGNC:8091): (ornithine aminotransferase) This gene encodes the mitochondrial enzyme ornithine aminotransferase, which is a key enzyme in the pathway that converts arginine and ornithine into the major excitatory and inhibitory neurotransmitters glutamate and GABA. Mutations that result in a deficiency of this enzyme cause the autosomal recessive eye disease Gyrate Atrophy. Alternatively spliced transcript variants encoding different isoforms have been described. Related pseudogenes have been defined on the X chromosome. [provided by RefSeq, Jan 2010]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 10-124403821-G-A is Pathogenic according to our data. Variant chr10-124403821-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 56135.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr10-124403821-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
OAT	NM_000274.4	c.748C>T	p.Arg250Ter	stop_gained	6/10	ENST00000368845.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
OAT	ENST00000368845.6	c.748C>T	p.Arg250Ter	stop_gained	6/10	1	NM_000274.4	P1
OAT	ENST00000539214.5	c.334C>T	p.Arg112Ter	stop_gained	5/9	1
OAT	ENST00000467675.5	n.549C>T		non_coding_transcript_exon_variant	5/7	5
OAT	ENST00000483711.1			downstream_gene_variant		5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251456 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135912

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1461768 Hom.: 0 Cov.: 32 AF XY: 0.00000825 AC XY: 6 AN XY: 727186

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000108

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Ornithine aminotransferase deficiency Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Sep 10, 2023	- -
Likely pathogenic, no assertion criteria provided	literature only	Juha Muilu Group; Institute for Molecular Medicine Finland (FIMM)	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 15, 2023	This sequence change creates a premature translational stop signal (p.Arg250*) in the OAT gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in OAT are known to be pathogenic (PMID: 1737786, 23076989). This variant is present in population databases (rs386833617, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with gyrate atrophy (PMID: 22182799). ClinVar contains an entry for this variant (Variation ID: 56135). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.38
Cadd	Pathogenic	41
Dann	Uncertain	1.0
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Uncertain	0.77	D
MutationTaster	Benign	1.0	A;A
Vest4		0.97
GERP RS		2.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.16		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: rs386833617; hg19: chr10-126092390;