The molecular factors involved in the pathophysiology of major depressive disorder (MDD) and related endophenotypes remain poorly understood. The complexity of the MDD phenotype may contribute to inconsistent results. Dr Mara Dierssen will do an overview concerning transcriptional factor mechanisms underpinning of neurodevelopmental disorders. One recent approach to examine the molecular basis of MDD is co-expression network analysis, which facilitates the examination of complex interactions between expression levels of individual genes and how they influence biological pathways that could be affected in MDD. Dr Bernhard Baune will present recent findings supporting dysregulated immune response and protein processing in the endoplasmic reticulum in MDD, thus providing novel insights into the pathophysiology of depression. Genome-wide transcriptome analysis of MDD patients clinically well characterize as well as of relevant risk phenotypes such as childhood traumatic experiences could represent an advance in this field. Dr Alessandra Minelli will present results from a transcriptomic study on the effect of childhood traumas. Moreover, she will show the role of environmental and genetic factors on the identified dysregulations. Based on the hypothesis that MDD could be characterized by accelerated aging, Dr Alessio Squassina investigated the role of telomere length and inflammation in this disorder. Findings showed that MDD patients have shorter telomeres compared to controls, and that treatment-resistant patients have higher levels of TNFα than non-TRD and controls, suggesting that TR might be associated with increased inflammation.