About GOA

Manual Annotation Efforts


Manual annotation is the direct assignment of GO terms to proteins, ncRNA and protein complexes by curators from evidence extracted during the review of published scientific literature, with an appropriate evidence code assigned to give an assessment of the strength of the evidence.

Manual curation by the GOA group is according to the following rules:

  1. The GOA project provides GO annotation to the UniProt Knowledgebase. UniProtKB accessions are the primary sequence identifier used for proteins. We also annotate to protein isoforms (e.g. Q4VCS5-2 ), post-processed chains (PRO_0000030311), to protein complexes using Complex Portal identifiers (CPX-593) and to ncRNAs using RNAcentral identifiers (URS00000064B1_559292)
  2. Papers are read in full and data may be extracted from any section, including the Supplementary Materials
  3. The curator will always assign the most specific term that describes a piece of biology proven in that paper, having first read the evidence presented in the paper.


If you are interested in any gene products which have not been manually annotated recently, please e-mail goa@ebi.ac.uk and we will endeavour to add them to our priority lists.

For additional information, please visit
tutorial and webinar on QuickGO

Electronic Annotation Methods

The majority - more than 99% - of GO annotations in the GOA database are made using electronic annotation methods.

There are a number of different techniques used to associate GO terms with gene products, including:

    - projection of annotations from one species to another based on orthology
    - prediction of GO terms based on manually-curated rules
    - prediction of GO terms based on sequence features
    - mapping of corresponding concepts in other controlled vocabularies to GO terms

Each GO annotation created by an electronic method has the following attributes:

    - an ECO (evidence) code indicating that an automated assertion method was used
    - a GO_REF reference that gives an overview of the prediction / association methodology
    - a with/from attribute that gives additional, context-dependent, information about the source of the association

We currently integrate annotations from the following nine electronic annotation pipelines:

Source Description/Reference QuickGO Link
InterPro2GO GO_REF:0000002

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=InterPro

UniProt Keywords2GO GO_REF:0000037
GO_REF:0000038

https://www.ebi.ac.uk/QuickGO/annotations?evidenceCode=ECO:0000501&withFrom=UniProtKB-KW

UniProt Subcellular Location2GO GO_REF:0000039
GO_REF:0000040

https://www.ebi.ac.uk/QuickGO/annotations?evidenceCode=ECO:0000501&withFrom=UniProtKB-SubCell

EC2GO GO_REF:0000003

https://www.ebi.ac.uk/QuickGO/annotations?evidenceCode=ECO:0000501&withFrom=EC

UniRule2GO GO_REF:0000104

https://www.ebi.ac.uk/QuickGO/annotations?evidenceCode=ECO:0000501&withFrom=UniRule

Ensembl & EnsemblGenomes GO_REF:0000107

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=Ensembl

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=EnsemblFungi

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=EnsemblMetazoa 

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=EnsemblPlants

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=EnsemblProtists

UniPathway2GO GO_REF:0000041

https://www.ebi.ac.uk/QuickGO/annotations?evidenceCode=ECO:0000501&withFrom=UniPathway

Gene Ontology Consortium GO_REF:0000108

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=GOC

RNACentral GO_REF:0000108

https://www.ebi.ac.uk/QuickGO/annotations?assignedBy=RNAcentral