ORIGINAL ARTICLESPharmacogenetic study focused on fluoxetine pharmacodynamics in children and adolescent patients impact of the serotonin pathwayMas, Sergi; Blázquez, Ana; Rodríguez, Natalia; Boloc, Daniel; Lafuente, Amalia; Arnaiz, Joan A.; Lázaro, Luisa; Gassó, PatriciaAuthor Information Departments of aPathological Anatomy, Pharmacology and Microbiology bPsychiatry and Clinical Psychobiology, University of Barcelona cDepartment of Child and Adolescent Psychiatry and Psychology, Institute of Neurosciences dDepartment of Clinical Pharmacology, Hospital Clinic de Barcelona eAugust Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona fMental Health Networking Biomedical Research Centre (CIBERSAM), Madrid, Spain Correspondence to Patricia Gassó, PhD, Department of Pathological Anatomy, Pharmacology and Microbiology, University of Barcelona, E-08036 Barcelona, Spain Tel: +34 93 402 4526; fax: +34 93 403 5881; e-mail: [email protected] or Joan A. Arnaiz, PhD, Department of Pathological Anatomy, Pharmacology and Microbiology, University of Barcelona, E-08036 Barcelona, Spain Tel: +34 93 402 4526; fax: +34 93403 5881; e-mail: [email protected] Received March 31, 2016 Accepted July 25, 2016 Pharmacogenetics and Genomics: November 2016 - Volume 26 - Issue 11 - p 487-496 doi: 10.1097/FPC.0000000000000240 Buy SDC Metrics Abstract Objective Pharmacogenetic studies of fluoxetine in children and adolescents are scarce. After reporting the effect of genetic variants in genes related to the fluoxetine pharmacokinetics on clinical response in a pediatric population, we now evaluate the impact of genetic markers involved in its pharmacodynamics. Patients and methods The assessment was performed in 83 patients after 12 weeks of fluoxetine treatment. The genetic association analysis included a total of 316 validated single nucleotide polymorphisms in 45 candidate genes involved in six different pathways. Results Clinical improvement after treatment with fluoxetine in our pediatric population was associated significantly with two polymorphisms located in genes related to the serotonergic system: the 5-hydroxytryptamine receptor 1B (HTR1B) and the tryptophan 5-hydroxylase 2 (TPH2). Conclusion Although a wide range of candidate genes related to different pathways were assessed, the results show that genetic markers directly related to serotonin have an important effect on fluoxetine response. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.