Each BEL Assertion can optionally be annotated to express knowledge about the statement itself. Some important uses of annotations are to specify information about the:
- Biological system in which the observation represented by the statement was made,
- Experimental methods used to demonstrate the observation, and
Examples of annotations that could be associated with a BEL Assertion are the:
- Species, tissue, and cellular location in which the observations were made, and
- Dosage, exposure and recovery time associated with the observation.