Genetics of Self-injurious Behaviour

Nonsuicidal Self-Injury (NSSI) is being increasingly regarded as a separate psychiatric disorder. Since the latest Diagnostic and Statistical Manual of Mental Disorders - DSM-5 from 2013 defined NSSI as a separate diagnosis under section III - Conditions for Further Study, the knowledge about this field has increased considerably; however, the aetiology of this behaviour has still not been explained. There are many psychological explanations for the development and the continuation of NSSI. Researchers have identified the most common comorbidities (depression, borderline personality disorder, anxiety). The causes of NSSI are not known, although studies that have been carried out so far indicate both genetic and environmental factors. The research included 95 adolescents with NSSI (participants were diagnosed based on the DSM-5 criteria), an original control group consisting of 21 people without NSSI, and 118 individuals from the general population as an additional control group for genetic research. For all participants we carried out the genotyping of polymorphisms for the TPH1 (rs4537731, rs1799913, rs7933505), SLC6A4 (VNTR STin2), OPRM1 (rs1799971), GNβ3 (rs5443) and DRD2/ANKK1 (rs1800497) genes. The participants with NSSI and the control group without NSSI completed translated questionnaires for the Barratt Impulsiveness Scale (BIS-11), State-Trait Anxiety Inventory for Adults (STAI), MacLean Screening Instrument for BPD (MSI-BPD) and the Early Trauma Inventory Self Report-Short Form (ETISR-SF). The participants with NSSI also completed the questionnaire for the Inventory of Statements about Self-Injury (ISAS), and the Self-Injury Craving Questionnaire (SICQ). The investigators carried out an association analysis and G x E analyses. The aim of the research was to carry out the first G x E study on the etiology of NSSI in Slovene adolescents. We have hypothesized that NSSI could be associated with one of the candidate polymorphisms or a combination of candidate