gene expression alteration in suicide victims with psychosis

suicide is a major public health concern, with approximately one million people committing suicide world-wide each year .risk factors for suicidal behavior include, psychiatric and medical illness, impulsivity, aggression, alcohol and drug abuse specially stimulants, and  stress. neurobiological, brain mappings and biochemical studies have revealed that suicide victims experiencing a large number of changes in metabolic pathways that end to committing suicide. our study aimed to discover gene expression changes in these subjects. blood samples collected from 84 saved suicide victims with at least one attempt to suicide in last 12 months that suffering from psychosis (50 scz, 19mdd, 15 bpd) and 70  gender , age , socioeconomic matched subjects with psychosis (40 scz,12mdd,18bpd) without any suicidal  thoughts . after rna extraction and cdna  synthesis, gene expression profiling analysis was done using the affymetrix genechip human genome u133 plus 2.0 array platform containing probes representing 39,000 genes. preparation of labeled and fragmented arna targets, hybridization, and scanning were carried out according to the manufacturer's protocol (affymetrix santa clara, ca).microarray results confirmed by real time pcr. gene ontology analysis was conducted for differentially expressed genes(fold change greater than 2 and a p value less than 0.05) using the enrichment algorithm integrated in the online database for annotation, visualization and integrated discovery (david 6.7) results showed significantly over expression of 65 genes including dopamine receptors and mitochondrial complex i and ii genes in suicide victims. also significantly low expression of 21 genes including comt, nrg1 and grm3 has been detected in suicide victims. regulation of dopamine metabolic process and central nervous system development were main terms indicated in enriched gene ontology calculations. it seems that gene expression changes in neurodevelopmental and dopaminergic pathways are correlated to suicide tendency and this is related to neuorobilogical  functions and decision making processes of brain. results of this project can help to predict the possibility of committing suicide in psychotic patients and suggesting potential markers for suicide thoughts.