PS71. A Clinical Pilot Study of Plasma Mitochondrial DNA as a Biomarker for Bipolar Disorder

There is an urgent need for biomarkers of bipolar disorder to optimize its treatment. Although inflammatory markers have been most established biomarkers of bipolar disorder, molecular basis of cytokine elevation is not known. We hypothesized that plasma mitochondrial DNA (mtDNA), one of mitochondrial damage-associated molecular patterns, would contribute to inflammation observed in bipolar disorder. The purpose of the present study was to evaluate whether plasma mtDNA is useful as a biomarker. We measured plasma mtDNA level (copy number) in two sets of samples. In the first set, (11 medicated patients with bipolar disorder and 10 healthy controls), plasma mtDNA was measured by quantitative PCR and plasma IL-6, TNF-α, and CRP were measured by ELISA. In the second set, subjects with no medication; six bipolar disorder, 19 healthy controls, five major depressive disorder, and 16 schizophrenia, plasma mtDNA was measured. This study was approved by the ethics committees of Hannan Hospital, Osaka City University, RIKEN, and National Center of Neurology and Psychiatry and conducted in accordance with the Declaration of Helsinki. In the first set, there was no significant difference in plasma mtDNA level between patients with bipolar disorder and healthy controls. IL-6 showed a non-significant tendency of higher level in patients with bipolar disorder compared with controls (p = 0.06) and there was a trend of positive correlation between plasma mtDNA level and IL-6 level (r = 0.45). There was no significant differences in mtDNA level in the second set as well. In summary, these findings did not support our hypothesis that plasma mtDNA would be a biomarker of bipolar disorder. To draw a conclusion, however, further studies in cerebrospinal fluid would be needed. The positive correlation between mtDNA level and IL-6 level warrants investigation in larger samples. PS72 Sibling Risk of Patients with Bipolar Patients in Taiwan: First Large-Scale National Population-Based Study from 2001 to 2011 Wen-Han Chang, Ya-Mei Bai, Mu-Hong Chen, Tzeng-Ji Chen, ChihMing Cheng, Cheng-Ta Li, Tung-Ping Su Taipei Veterans General Hospital, Taiwan Abstract Objective: The degree of genetic transmission of bipolar disorders in Han Chinese appear to be at higher risk of major psychiatric disorders, but estimates of individual sibling risks are unclear or of limited reliability. Hence we estimate the sibling risk for major psychiatric disorders of patients with DSM-IV diagnosis of bipolar in Taiwan from 2001 to 2011. Method: Using data from the National Health Insurance (NHI) Research Database in Taiwan from 1996 to 2011, we conducted a nationwide cross-sectional study of data collected from 23,258,175 beneficiaries. The relationship of full siblings was identified based on shared parents. Only two or more siblings retrieved from 3 one-million cohorts (2000, 2005, 2010 year) were enrolled into the studying sibling cohort, including a total of 112,910 full sibling pairs among 221,755 subjects. Odds Ratios (ORs) with 95% CIs were calculated to identify the bipolar sibling risk for major psychiatric disorders. Result: Subjects with at least one sibling with bipolar were more likely to have 8-fold prevalence of suffering bipolar (prevalence, 3.1% v.s. 0.4%). ORs were 7.26 (5.08–10.38) for developing bipolar, 4.54 (3.49–5.90) for MDD, 4.62 (3.12–6.85) for schizophrenia. The effect of the same-sex sibling was found for developing bipolar disorders. ORs of bipolar for the same-sex siblings were 10.67 and 8.08 among male and female bipolar siblings; however, for different-sex siblings, ORs were decreased to 5.3 in both male and female siblings. In addition, OR for a bipolar sibling to suffer schizophrenia was around 6 except for a female having a bipolar sister (OR 1.32, 95%CI 0.3–5.3). Conclusion: This is the first large‐scale epidemiological study providing the evidence of a significant degree of risk in genetic transferring among the bipolar sibling. Those who have bipolar sibling are a high-risk population and further, male bipolar siblings are also high-risk for developing schizophrenia.Objective: The degree of genetic transmission of bipolar disorders in Han Chinese appear to be at higher risk of major psychiatric disorders, but estimates of individual sibling risks are unclear or of limited reliability. Hence we estimate the sibling risk for major psychiatric disorders of patients with DSM-IV diagnosis of bipolar in Taiwan from 2001 to 2011. Method: Using data from the National Health Insurance (NHI) Research Database in Taiwan from 1996 to 2011, we conducted a nationwide cross-sectional study of data collected from 23,258,175 beneficiaries. The relationship of full siblings was identified based on shared parents. Only two or more siblings retrieved from 3 one-million cohorts (2000, 2005, 2010 year) were enrolled into the studying sibling cohort, including a total of 112,910 full sibling pairs among 221,755 subjects. Odds Ratios (ORs) with 95% CIs were calculated to identify the bipolar sibling risk for major psychiatric disorders. Result: Subjects with at least one sibling with bipolar were more likely to have 8-fold prevalence of suffering bipolar (prevalence, 3.1% v.s. 0.4%). ORs were 7.26 (5.08–10.38) for developing bipolar, 4.54 (3.49–5.90) for MDD, 4.62 (3.12–6.85) for schizophrenia. The effect of the same-sex sibling was found for developing bipolar disorders. ORs of bipolar for the same-sex siblings were 10.67 and 8.08 among male and female bipolar siblings; however, for different-sex siblings, ORs were decreased to 5.3 in both male and female siblings. In addition, OR for a bipolar sibling to suffer schizophrenia was around 6 except for a female having a bipolar sister (OR 1.32, 95%CI 0.3–5.3). Conclusion: This is the first large‐scale epidemiological study providing the evidence of a significant degree of risk in genetic transferring among the bipolar sibling. Those who have bipolar sibling are a high-risk population and further, male bipolar siblings are also high-risk for developing schizophrenia. PS73 Changes in neuronal densities underlying transcriptional alterations in psychiatric patients Lilah Toker, Paul Pavlidis, Ogan Mancarci, Shreejoy Tripathy University of British Columbia, Canada Abstract Introduction: High-throughput expression techniques are widely used to study psychiatric disorders. Genes found to be differentially expressed are next subjected to various networkenrichment analyses using resources such as Gene Ontology and protein-protein interaction databases. Such analyses are basedIntroduction: High-throughput expression techniques are widely used to study psychiatric disorders. Genes found to be differentially expressed are next subjected to various networkenrichment analyses using resources such as Gene Ontology and protein-protein interaction databases. Such analyses are based