The present work examined a novel, specific and a priori GxE that was hypothesized to affect youths' level of positive affect based on the differential susceptibility hypothesis (DSH).23, 24, 25, 26 The majority of prior GxE research has been guided implicitly by a vulnerability-stress framework.27, 28 This traditional vulnerability perspective highlights that certain individuals, frequently for genetic reasons, are more vulnerable to psychopathology and poor outcomes compared with others, and this risk is exerted only in response to the negative effects of environmental influences. In contrast, the DSH proposes that some individuals, often for genetic reasons, are more responsive to environmental experiences in a ‘for better and worse' fashion.29 These genetically susceptible individuals are expected to exhibit poor functioning and psychopathology under adverse environmental conditions (for example, negative events), but also to flourish and benefit from the positive environmental conditions (for example, supportive parenting).
