NM_000274.4:c.1192C>T

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PVS1_StrongPM2PP5_Very_Strong

The NM_000274.4(OAT):​c.1192C>T​(p.Arg398*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,614,020 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 (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

OAT
NM_000274.4 stop_gained

Scores

5
1
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 9.39

Publications

5 publications found
Variant links:
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]
OAT Gene-Disease associations (from GenCC):
  • ornithine aminotransferase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 14 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 10 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 10-124398070-G-A is Pathogenic according to our data. Variant chr10-124398070-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 456519.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
OATNM_000274.4 linkc.1192C>T p.Arg398* stop_gained Exon 10 of 10 ENST00000368845.6 NP_000265.1 P04181-1A0A140VJQ4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
OATENST00000368845.6 linkc.1192C>T p.Arg398* stop_gained Exon 10 of 10 1 NM_000274.4 ENSP00000357838.5 P04181-1
OATENST00000539214.5 linkc.778C>T p.Arg260* stop_gained Exon 9 of 9 1 ENSP00000439042.1 P04181-2
OATENST00000471127.1 linkn.702C>T non_coding_transcript_exon_variant Exon 4 of 4 2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152144
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
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
GnomAD2 exomes
AF:
0.00000797
AC:
2
AN:
250954
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461758
Hom.:
0
Cov.:
31
AF XY:
0.00000688
AC XY:
5
AN XY:
727182
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53382
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111934
Other (OTH)
AF:
0.00
AC:
0
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.489
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152262
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74470
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41550
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00000964
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000165
AC:
2

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Ornithine aminotransferase deficiency Pathogenic:4
Oct 01, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Arg398*) in the OAT gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 42 amino acid(s) of the OAT protein. This variant is present in population databases (rs200068769, gnomAD 0.006%). This premature translational stop signal has been observed in individuals with gyrate atrophy of the choroid and the retina (PMID: 7887415). ClinVar contains an entry for this variant (Variation ID: 456519). Algorithms developed to predict the effect of variants on protein structure and function are not available or were not evaluated for this variant. Experimental studies have shown that this premature translational stop signal affects OAT function (PMID: 7887415, 23076989). For these reasons, this variant has been classified as Pathogenic. -

Mar 17, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 18, 2020
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Neuberg Centre For Genomic Medicine, NCGM
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The stop gained variant c.1192C>T (p.Arg398Ter) in OAT gene has been reported in an individual affected with gyrate atrophy of the choroid and the retina (Michaud J et.al.,1995). Experimental studies have shown that this nonsense change leads to a drastic reduction of the OAT enzymatic activity (Doimo M et.al.,2013). This variant has been reported to the ClinVar database as Pathogenic. The p.Arg398Ter variant is novel (not in any individuals) in 1000 Genomes and allele frequency of 0.000797% is reported in gnomAD. The nucleotide change in OAT is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Pathogenic -

Hyperornithinemia Pathogenic:1
Sep 28, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: OAT c.1192C>T (p.Arg398X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein. Truncations downstream of this position have been classified as pathogenic in ClinVar and is associated with Gyrate atrophy in HGMD. The variant allele was found at a frequency of 8e-06 in 250954 control chromosomes (gnomAD). c.1192C>T has been reported in the literature in individuals affected with Ornithine Aminotransferase Deficiency (examples: Michaud_1995 and Cleary_2005). These data indicate that the variant is associated with disease. Multiple publications have provided experimental evidence that this variant abolishes the protein function (example: Doimo_2012 and Cleary_2005). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.51
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
45
DANN
Uncertain
1.0
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.84
FATHMM_MKL
Pathogenic
0.97
D
PhyloP100
9.4
Vest4
0.94
GERP RS
4.2
Mutation Taster
=0/200
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs200068769; hg19: chr10-126086639; API