Average Nucleotide Identity (ANI)
Average Nucleotide Identity (ANI)
The NCBI utilizes ANI to evaluate the taxonomic identity of prokaryotic genome assemblies in GenBank. The result of ANI analysis is described by the Taxonomy check status and the reason for this Taxonomy check status is described in the best match status.
For more information about this process, see Konstantinidis and Tiedje 2005 and Ciufo et al 2018.
There are 3 possible taxonomy check statuses:
OK—The best match is consistent with the submitted species.
Inconclusive—The ANI result doesn’t clearly show a match with a species.
Failed—The best match is inconsistent with the submitted species.
When the taxonomy check status is “OK,” the ANI result fits one of the following best match statuses:
Species-match—The assembly matches the submitted species.
Subspecies-match—The assembly matches a subspecies under the submitted species.
Synonym-match—The assembly matches an ANI synonym of the submitted species.
Derived-species-match—The assembly matches a subspecies of the submitted species or a different subspecies than the submitted subspecies.
Genus-match—An informal species name was submitted and the assembly matches at the genus level.
Approved-mismatch—The assembly matches a different species, but the mismatch was manually reviewed and the submitted species was accepted.
When the taxonomy check status is “Inconclusive,” the ANI result fits one of the following best match statuses:
Below-threshold-match—The assembly matches the submitted species below the ANI threshold.
Low-coverage—The assembly matches the submitted or a different species below the coverage threshold of 10%.
When the taxonomy check status is “Failed,” the ANI result fits one of the following best match statuses:
Mismatch—The assembly matches a different species.
Below-threshold-mismatch—The assembly matches a different species below ANI threshold.