Bipolar disorder (BD) formerly known as manic-depressive illness is a mood disorder that is characterized by severe swings of elated behaviour termed mania and deep depression. The etiology of the disorder show a large genetic component with recent studies suggesting gene-environment interactions are important. The World Health Organization (WHO) indicate that bipolar disorder is the 6th leading cause of disability in the world and thus significant research funding has been invested at the National Institute of Mental Health in the USA, to understand its cause, treatment and underlying molecular mechanisms.

Several findings from funded research were recently presented at the 5th Biennial Conference of the International Society for Bipolar Disorders, which took place on 14th to 17th March 2012 in the beautiful surroundings of Istanbul, the Turkish city built on seven hills. The interesting program consisted of 4 keynote lectures, 6 core symposia and 16 parallel symposia which attracted more than 900 participants including psychiatrists and clinical researchers. The opening keynote lectures focussed on an evocative debate on pediatric bipolar disorder, which highlighted the disabling disorder in children and adolescents and the need for a well defined diagnosis. 

The first core symposium on optimizing functional outcomes in bipolar disorder commenced with a fascinating presentation by Prof Michael Berk on lifestyle factors such as diet, exercise and smoking that contribute to mood disorders. Other highlights of the meeting included a symposium devoted to the development and determinants of psychopathology in prospective bipolar offspring cohorts. The hot topic of personalized medicine in psychiatry was discussed by Prof Charles Nemeroff on prediction of disease vulnerability and treatment response in bipolar disorders; whereas the session on biomarkers in mood disorders emphasized integrative analyses across molecular, imaging and clinical domains. The molecular basis of bipolar disorder was addressed by Prof Tadafumi Kato who presented research from his group on mitochondrial dysfunction in bipolar disorder, where they observed differences in DNA methylation status in postmortem brains, and neuron specific accumulation of mitochondrial DNA mutations in a mouse model of bipolar disorder.

In a timely fashion, a core symposium was dedicated to the update of criteria of Diagnostic and Statistical Manual of Mental Disorders (DSM-5) that will be published in May 2013. With the launch of our cross-journal thematic series on “Towards a new psychiatry”, new submissions on this important topic are being considered. Treatment response to mood stabilizers was addressed throughout the meeting with Prof John Kelsoe showing new data of an association between elated mania with and a single nucleotide polymorphism in neurotrophic tyrosine kinase, receptor, type 2 (NTKR2) in bipolar patients that responded positively to lithium. Further breaking news highlighted the deoxynucleotidyltransferase terminal, interacting protein 2 (DNTTIP2), a gene involved in the expression of the oestrogen receptor. Differential DNA methylation levels of this gene were observed in blood samples from monozygotic twins discordant for bipolar disorder, which was replicated in post-mortem brain samples from bipolar disorder patients and additionally significantly associated with total brain volume.

This exciting meeting generated novel clues that will help to further delineate the basis and functional molecular consequences of bipolar disorder and its treatment. The great opportunities to meet key opinion leaders in psychiatry at the conference resulted in welcoming Profs Charles Nemeroff, Michael Berk, John Kelsoe, Martin Preisig and Michael Bauer as editorial board members to BMC Medicine. We look forward to stimulating collaborations and future international meetings.