The association between childhood maltreatment and empathic perspective taking is moderated by the 5-HTT linked polymorphic region: Another example of "differential susceptibility"

Previous research has suggested that the short (S)-allele of the 5-HT transporter gene-linked polymorphic region (5-HTTLPR) may confer "differential susceptibility" to environmental impact with regard to the expression of personality traits, depressivity and impulsivity. However, little is known about the role of 5-HTTLPR concerning the association between childhood adversity and empathy. Here, we analyzed samples of 137 healthy participants and 142 individuals diagnosed with borderline personality disorder (BPD) focusing on the 5-HTTLPR genotype (S/L-carrier) and A/G SNP (rs25531), in relation to childhood maltreatment and empathy traits. Whereas no between-group difference in 5-HTTLPR genotype distribution emerged, the S-allele selectively moderated the impact of childhood maltreatment on empathic perspective taking, whereby low scores in childhood trauma were associated with superior perspective taking. In contrast, L-homozygotes seemed to be largely unresponsive to variation in environmental conditions in relation to empathy, suggesting that the S-allele confers "differential susceptibility". Moreover, a moderation analysis and tests for differential susceptibility yielded similar results when transcriptional activity of the serotonin transporter gene was taken into account. In conclusion, our findings suggest that the S-allele of the 5-HTTLPR is responsive to early developmental contingencies for "better and worse", i.e. conferring genetic plasticity, especially with regard to processes involving emotional resonance

Childhood Adversity and Borderline Personality Disorder:A Meta‐Analysis

Objective: The aim of this meta-analysis was to better understand the magnitude and consistency of the association between childhood adversity and borderline personality disorder (BPD) across case-control, epidemiological and prospective cohort studies. Method: Following the review protocol (reference: CRD42017075179), search terms pertaining to adversity and BPD, were entered into three search engines. Random effects meta-analysis synthesised the size and consistency of the effects. Results: 97 studies compared BPD to non-clinical (k = 40) and clinical (k = 70) controls. Meta-analysis of case control studies indicated that individuals with BPD are 13.91 (95% CI 11.11-17.43) times more likely to report childhood adversity than non-clinical controls. This effect was smaller when considering retrospective cohort (OR: 2.59; 95% CI .93-7.30) and epidemiological (OR: 2.56, 95% CI 1.24-5.30) studies. Findings were significant across adversity subtypes with emotional abuse (OR: 38.11, 95% CI: 25.99-55.88) and neglect (OR: 17.73, 95% CI=13.01-24.17) demonstrating the largest effects. Individuals with BPD were 3.15 (95% CI 2.62-3.79) times more likely to report childhood adversity than other psychiatric groups. Conclusions: This meta-analysis corroborates theoretical proposals that exposure to adverse life experiences is associated with BPD. It highlights the importance of considering childhood adversity when treating people diagnosed with BPD