What is the Sequence Ontology?
The Sequence Ontology (SO) project aims to unify the way in which we describe sequence annotations, by providing a controlled vocabulary of terms and the relationships between them. The terms in the ontology describe the features and properties of biological sequence. Features occupy a length of sequence such as ‘exon’, whereas properties describe attributes of the features. For example a gene may have the property ‘maternally_expressed’. Alone the phrase ‘maternally_expressed’ cannot be located onto a sequence, but must be associated with a feature. The concepts in the ontology are structure by relationships, which allow classification hierarchies to be built. Each relationship has a defined meaning, which allows the connection between the two concepts to be understood. The position of a concept in relation to others also provides some context to the meaning of the concept. The defined relationships between the features are: subclass [is_a], membership [part_of], topological [adjacent
