Objectives: The short allele of the serotonin transporter linked polymorphic region, 5HTTLPR has been associated with anxiety, major depressive disorder and suicidality. The impulsive self- and other-damaging behaviors seen in borderline personality disorder and antisocial personality disorder also have substantial comorbidity with depression but are associated with more severe environmental stressors. This study tested the hypothesis of an association between the short allele of the 5HTTLPR and borderline or antisocial traits in young adulthood.
Methods: The 5HTTLPR was genotyped among 96 young adults from low to moderate income families (62 adults without and 34 adults with borderline personality disorder or antisocial personality disorder traits). Traits of borderline and antisocial personality disorders were assessed with the Structured Clinical Interview for Diagnosis-Axis II.
Results: The number of short 5HTTLPR alleles were significantly related to incidence of borderline personality disorder or antisocial personality disorder traits and also to each set of traits independently. Male sex and quality of care in infancy were also associated with incidence of borderline personality disorder and antisocial personality disorder traits but did not account for the association with the short allele. Depressive disorders were not associated with the short allele in this sample.
Conclusions: Young adults of lower socioeconomic status who carry the short 5HTTLPR allele may be especially vulnerable to developing antisocial or borderline traits by young adulthood.