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Ontological Relationships

In most cases, these relationships will be introduced by the BEL Namespace resources, and are not needed for creation of BEL Statements and BEL Scripts.


For terms A and B, A isA B indicates that A is a subset of B.

All terms in BEL 1.0 represent classes, but given that classes implicitly have instances, A isA B is interpreted to mean that any instance of A must also be an instance of B. This relationship can be used to represent GO and MeSH hierarchies:

pathology(MESH:Psoriasis) isA pathology(MESH:"Skin Diseases")


For terms A and B, A partOf B indicates that A is a part of B.

p(HGNC:CHUK)  partOf complex(GO:"IkappaB kinase complex")
p(HGNC:IKBKB) partOf complex(GO:"IkappaB kinase complex")
p(HGNC:IKBKG) partOf complex(GO:"IkappaB kinase complex")


For terms A and B, A equivalentTo B / A eq B indicates that A and B are equivalent. This relationship is two-way.