rs121965039

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5

The NM_000274.4(OAT):​c.461G>T​(p.Arg154Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,612,724 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

OAT
NM_000274.4 missense

Scores

13
5
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:1

Conservation

PhyloP100: 5.68
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1
In a helix (size 17) in uniprot entity OAT_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000274.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 10-124408601-C-A is Pathogenic according to our data. Variant chr10-124408601-C-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 152.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=2, Uncertain_significance=1}. Variant chr10-124408601-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
OATNM_000274.4 linkc.461G>T p.Arg154Leu missense_variant Exon 4 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.461G>T p.Arg154Leu missense_variant Exon 4 of 10 1 NM_000274.4 ENSP00000357838.5 P04181-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151892
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000657
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000274
AC:
4
AN:
1460832
Hom.:
0
Cov.:
30
AF XY:
0.00000275
AC XY:
2
AN XY:
726738
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
151892
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74192
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000657
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000329
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:3Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Ornithine aminotransferase deficiency Pathogenic:2Uncertain:1
Feb 15, 1992
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Nov 22, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Experimental studies have shown that this missense change affects OAT function (PMID: 1737786, 34395527). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt OAT protein function. ClinVar contains an entry for this variant (Variation ID: 152). This missense change has been observed in individual(s) with gyrate atrophy of the choroid and retina (PMID: 1737786). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 154 of the OAT protein (p.Arg154Leu). -

Dec 13, 2023
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hyperornithinemia Pathogenic:1
Aug 06, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: OAT c.461G>T (p.Arg154Leu) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251370 control chromosomes. c.461G>T has been reported in the literature in one homozygous individual affected with Ornithine Aminotransferase Deficiency (Brody_1992). These data indicate that the variant may be associated with disease. Functionally, the variant was found to inhibit normal enzymatic activity in both cell culture and in vitro assays. Fibroblasts from a homozygous patient and transfected CHO cells had no observable enzymatic activity (Brody_1992). This was further investigated by using purified proteins produced in E. coli, where the variant protein was shown to have deficits in forming functional tetramers, instead forming non-functional dimers (Montioli_2021). The variant also had 350-fold lower catalytic activity in vitro (Montioli_2021). The following publications have been ascertained in the context of this evaluation (PMID: 1737786, 34395527). ClinVar contains an entry for this variant (Variation ID: 152). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.90
BayesDel_addAF
Pathogenic
0.53
D
BayesDel_noAF
Pathogenic
0.53
CADD
Pathogenic
30
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.95
.;D
Eigen
Uncertain
0.68
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Pathogenic
0.48
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.9
.;M
PrimateAI
Uncertain
0.75
T
PROVEAN
Pathogenic
-6.7
D;D
REVEL
Pathogenic
0.94
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
.;D
Vest4
0.79
MutPred
0.96
.;Loss of MoRF binding (P = 0.0242);
MVP
0.98
MPC
0.92
ClinPred
0.97
D
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.96
gMVP
0.99

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.

Other links and lift over

dbSNP: rs121965039; hg19: chr10-126097170; API