How close are we to individual analgesic adjustment according to a patient's genotype?

Samer CF Clinical Pharmacology & Toxicology, Geneva University Hospitals, Switzerland and Swiss Center for Applied Human Toxicology, University of Geneva, Switzerland.
Dayer P Clinical Pharmacology & Toxicology, Geneva University Hospitals, Switzerland.
Desmeules JA Clinical Pharmacology & Toxicology Geneva University Hospitals Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland and Swiss Center for Applied Human Toxicology, University of Geneva, Switzerland. jules.desmeules@hcuge.ch.