SA75 - ASSOCIATION OF SUICIDE MARKERS WITH COMPULSIVE SYMPTOMS IN HEALTHY SUBJECTS

Abstract

Background Suicide is one of the leading causes of death worldwide. A complex interplay between various risk factors is assumed to ultimately trigger a suicide attempt. Among those, genetic variations and personality traits seem to be the most relevant predictors. Results from a genome-wide association study we participated in (Galfalvy et al. 2015) point to several variations associated with the condition. In order to elucidate their underlying function a closer look on the influence on personality traits as one of the main predictors seemed feasible. Among others, stressful life events have been known to increase the risk of suicidal behavior. Therefore, we investigated whether 23 susceptibility markers associated with suicidal behavior also affect obsessive- compulsive behavior (as a personality trait prone to show a high risk of coping problems under stress) in healthy individuals. Methods Unrelated healthy volunteers of German descent were screened for an absence of any psychiatric disorder in themselves or their first degree relatives. Obsessive and compulsive symptoms were elevated using the Maudsley Obsessive Compulsive Inventory (MOCI). Finally, 2104 subjects (52% female) were enrolled in the study. Genotype data was obtained using chip technology and imputation. After stringent quality controls 23 Single Nucleotide Polymorphisms (SNPs) were analyzed using an additive linear regression model. Benjamini-Hochberg procedure was used to correct for multiple testing. Results In females, significant associations with the MOCI total score were identified for two intergenic SNPs, localized near BRINP3 (associated with coronary heart disease and aggressive periodontitis) and LOC647132 (a processed pseudogene which is associated with antibody response to smallpox vaccine), both involved in inflammation processes. In males, significant associations could be detected for seven SNPs localized in the TBX20 gene linked to migration and development of brainstem motor neurons, cardiac development and multiple cardiac functions and pathologies. Discussion These results indicate a sex specific overlap of the genetic make-up between suicidality and obsessive-compulsive behavior, thereby emphasizing the relevance of personality traits for suicidal behavior. Further research approaches are necessary in order to replicate these findings and also to identify the underlying functional relevance of the associated variants.