The Chemical Entities of Biological Interest (ChEBI) ontology is downloaded weekly from EMBL-EBI at http://www.ebi.ac.uk/chebi/. The data is made available under the Creative Commons License (CC BY 3.0, http://creativecommons.org/licenses/by/3.0/). For more information see: Degtyarenko et al. (2008) ChEBI: a database and ontology for chemical entities of biological interest. Nucleic Acids Res. 36, D344–D350.
[[CYP2D6 gene polymorphism results in decreased activity of CYP2D6 protein] which results in decreased metabolism of Clonidine] which results in decreased chemical synthesis of 4-hydroxyclonidine; [CYP2D6 protein results in increased metabolism of Clonidine] which results in increased chemical synthesis of 4-hydroxyclonidine