Box 1: Challenges of pharmacogenomics studies in mood disorders
Potential challenges	Description
Establishing a hard-end definition of treatment outcome (response and remission)	Mood disorders are highly heterogeneous and there are no objective criteria to define both the diagnosis of the disorders and treatment outcomes. Assessment tools applied in the diagnosis and treatment follow-up of mood disorders have poor sensitivity and specificity
Optimizing sample size	Underpower is the major bottleneck for success in the pharmacogenomic studies in mood disorders and a global collaboration is required to improve the existing efforts
Bioinformatics tools for integrative analysis	To provide an evidence-based decision about a patient, a complete evaluation of data obtained from the different pillars of omics investigation, including genomics, epigenomes, proteomics, metabolomics, and microbiomes is required. Advanced bioinformatics tools are required to perform such kind of integrative analysis
Replication of findings and moving to clinical application	Findings from both candidate gene studies and GWASs are hardly replicated and translating the findings is inadequate