Genetic variation in 5HTTLPR is associated with emotional resilience

Abstract

Emotional resilience can be defined as the ability to maintain healthy and stable levels of psychological functioning in the wake of stress and trauma. Although genes that contribute to psychopathology (often in interaction with environmental stressors) are being detected with increasing consistency, genes that influence resilience to stress have been less studied. In this study, 423 undergraduate college students completed a psychometrically sound 10-item self-report measure of resilience (CDRISC-10) and provided blood for DNA. Linear and logistic regression analyses were used to model relationships between the serotonin transporter promoter polymorphism (5HTTLPR) and CDRISC-10 scores and categories, respectively. CDRISC-10 scores were normally distributed (mean 26.17, SD 5.88 [range 5-40]). In models adjusting for ancestry proportion scores (to mitigate confounding by population stratification) and other covariates, each copy of the "s" allele of 5HTTLPR was associated with approximately 1-point lower CDRISC-10 score. Each copy of the "s" allele was associated with increased (adjusted OR = 1.53, 95% CI 1.06-2.21, P = 0.024) odds of being in the low resilient category (>1 SD below the mean), compared to being homozygous for the "l" allele. These findings suggest that variation in 5HTTLPR is associated with individual differences in emotional resilience, defined as an individual's ability to withstand and bounce back from stress. This relationship may explain the frequently observed interaction between 5HTTLPR and life stressors in predicting adverse mental health outcomes (e.g., depressive symptoms). Replication is needed, in concert with identification of other genes that influence emotional resilience and related phenotypes.

FIGURE 1. Distribution of CDRISC-10 Scores in the Sample (N=423)

Distribution of CDRISC-10 scores in the sample of N = 423 subject. The red bar shows the mean value for the sample with the pink bars showing 1 standard deviation (SD) below and above the mean, respectively.