Review of the 6th symposium for the search for the causes of schizophrenia, Sao Paulo, Brazil, 3-6 February 2009.

In this review, we present the main findings of the 6th Symposium for the Search for the Causes of Schizophrenia, which took place between 3 and 6 February 2009, in Sao Paulo, Brazil. In a few short years, the landscape of the causes of schizophrenia has changed dramatically. The flat and featureless epidemiological horizon has developed undulating contours, which promise new avenues for research, particularly if we are able to integrate such findings with tantalising new findings from genetics as novel methods for identifying genuine sites of genetic risk emerge. The Search highlighted and fostered the emerging acknowledgement that we will need to integrate knowledge across traditionally disparate disciplines in psychiatry in order to develop complex, testable hypotheses in the search for the causes of schizophrenia. Such challenges are beginning to be addressed. From epidemiology, gene-environment studies are becoming more sophisticated, while neuroscience is increasingly concerned about social organisation and how social factors impinge upon biological pathways to potentially lead to psychosis. Tantalising new insights from genome-wide association studies offer new clues about rare genetic mutations, which have large effect sizes for schizophrenia, including copy number variants and de novo mutations. It is only through forums such as the 6th Symposium for the Search for the Causes of Schizophrenia that the seeds of integrated collaborations across disciplines can be sown to address the complex polyfactorial basis of schizophrenia.