Imaging genetics in depression

In recent years, the demand for more efficient psychiatric diagnostics and treatments has stimulated an unprecedented effort in clinical, genetic, and imaging research with the goal to realize the promise of precision medicine and develop new therapeutic approaches. Major depressive disorder (MDD), which is highly prevalent and ranks among the top causes of disability worldwide, has been one of the central subjects in this story. Since the turn of the millennium, researchers began to amalgamate methods from psychiatric genetics and clinical neuroimaging to uncover the effects of genetic variation at the level of brain function, structure or connectivity. This line of research, imaging genetics, matured to a distinct research field that became a major force in the quest for understanding the neurobiology underlying MDD and the implications of the serotonergic system. This chapter provides an overview of the development and impact of imaging genetics research with a focus on MDD and the serotonergic system and discusses the barriers and solutions on the way to clinical implementation.