GENE REFERENCE / HGNC:8091
OAT
ornithine aminotransferase
What does this gene do?
The OAT gene provides instructions for making the enzyme ornithine aminotransferase. This enzyme is active in the energy-producing centers of cells (mitochondria), where it helps break down a molecule called ornithine. Ornithine is involved in the urea cycle, which processes excess nitrogen (in the form of ammonia) that is generated when protein is broken down by the body.
In addition to its role in the urea cycle, ornithine participates in several reactions that help ensure the proper balance of protein building blocks (amino acids) in the body. This balance is important because a specific sequence of amino acids is required to build each of the many different proteins needed for the body's functions. The ornithine aminotransferase enzyme helps convert ornithine into another molecule called pyrroline-5-carboxylate (P5C). P5C can be converted into the amino acids glutamate and proline.
Related condition topics
MedlinePlus mentions this gene in the condition pages below. These links alone do not show that the gene causes a condition.
ClinGen reviews
ClinGen reviews the evidence linking a particular gene to a condition. Each rating below describes the strength of that link. It does not classify a variant in your DNA file.
| Condition | Inheritance | Evidence |
|---|---|---|
| ornithine aminotransferase deficiencyMONDO:0009796 · Evaluated 2019-07-10 | Autosomal recessive | DefinitiveAminoacidopathy Gene Curation Expert Panel |
ClinVar records
These numbers show what has been submitted to ClinVar. They cannot tell you how likely you are to have a condition.
- Submitted alleles
- 823
- Submissions for variants in or overlapping this gene
- 1,337
- Submissions explicitly reporting this gene
- 1,256
- Alleles reported pathogenic / likely pathogenic
- 174
- VariationIDs with uncertain significance
- 223
- VariationIDs with conflicting classifications
- 30
The rows count different things: alleles, submissions or VariationIDs. Their categories can overlap, so do not add them together. Pathogenic/likely pathogenic counts exclude structural variants that merely overlap a gene. A dash in the source means “not reported,” not zero.
NCBI produces the gene-summary file each week using counts recorded at the start of the month. The numbers may differ from those on the live ClinVar website. Read the field definitions ↗
YOUR DNA FILE
Can your DNA file tell you about OAT?
From a DNA test kit (such as 23andMe, AncestryDNA or MyHeritage). These kits check a fixed list of about 600,000 to 700,000 positions across your whole genome. ClinVar lists 174 alleles in OAT reported as pathogenic or likely pathogenic. A kit checks only some of these positions, and often none of them.
From whole genome sequencing (a VCF file). Sequencing reads most of your genome. Your file lists the places where your DNA differs from the reference genome. Some regions are hard to sequence, including parts of some genes that have near-identical copies elsewhere, and a VCF file does not record which positions were read well.
If a variant is not in your file, that does not mean you don’t have it.
What BioDecode checks
BioDecode compares every variant in your file with ClinVar, on your own computer. For each match, it shows the ClinVar classification, the review status and the condition it was reported for. Your file is not uploaded.
A ClinVar classification applies to one particular variant and the condition it was reported for. It does not tell you about other variants in OAT.
BioDecode cannot fill gaps in your test, diagnose a condition or replace clinical testing.
Sources and dates
The source information on this page last changed on 2026-10-17.
HGNC Source details
Source release: Fri, 16 Oct 2026 13:36:12 GMT
Source record updated: 2023-01-20
SHA-256: 72bfe0c05800163c040a2cf663c70501f9ac9236469fbd0b552f2cd37a4d7f67
MedlinePlus Source details
Source release: Sat, 17 Oct 2026 05:15:49 GMT
Source publication: 2020-08-18
Source review: 2009-08
SHA-256: fdc8bd614310c12718379cef6569962e5d0e791cecabcc355b53a72816ac263a
ClinVar Source details
Source release: Sun, 11 Oct 2026 06:36:01 GMT
SHA-256: b21584f8ebc89a636ce9706023fa9052460587e2ab0fe6d0edf4b9db34336c02
ClinGen Source details
Source release: Sat, 17 Oct 2026 07:46:29 GMT
SHA-256: 46d4c75fcae7dd62a9dea4988bbbd440bdc68f2db452fea1556d47b0406de60e
About the library sources · Latest validated release · Record 364d4ea3e2e6