Background: Early life stress (ELS) affects facial emotion recognition (FER), as well as the underlying brain network. However, there is considerable inter-individual variability in these ELS-caused alterations. As the hypothalamic-pituitary-adrenal (HPA) axis is assumed to mediate neural and behavioural sequelae of ELS, the genetic disposition towards HPA axis reactivity might explain differential vulnerabilities.
Methods: An additive genetic profile score (GPS) of HPA axis reactivity was built from 6 SNPs in 3 HPA axisrelated genes (FKBP5, CRHR1, NR3C1). We studied two independent samples. As a proof of concept, GPS was tested as a predictor of cortisol increase to a psychosocial challenge (MIST) in a healthy community sample of
n=40. For the main study, a sample of n=170 completed a video-based FER task and retrospectively reported ELS experiences in the Childhood Trauma Questionnaire (CTQ).
Results: GPS positively predicted cortisol increase in the stress challenge over and above covariates. CTQ and genetic profile scores interacted to predict facial emotion recognition, such that ELS had a detrimental effect on emotion processing only in individuals with higher GPS. Post-hoc moderation analyses revealed that, while a less stress-responsive genetic profile was protective against ELS effects, individuals carrying a moderate to high
GPS were affected by ELS in their ability to infer emotion from facial expressions.
Discussion: These results suggest that a biologically informed genetic profile score can capture the genetic disposition to HPA axis reactivity and moderates the influence of early environmental factors on facial emotion recognition. Further research should investigate the neural mechanisms underlying this moderation. The GPS used here might prove a powerful tool for studying inter-individual differences in vulnerability to early life stress.
early life stress
600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit
Interaction of HPA axis genetics and early life stress shapes emotion recognition in healthy adults
Charité - Universitätsmedizin Berlin
Gene-by-enviornment- and single-SNP-association studies have been found to rarely replicate. In the light of effect sizes found in genome-wide association studies they are now regarded as underpowered and it has been suggested to assume their findings are false positives unless replicated in an independent sample. For a broader critique of the field see e.g. Duncan, Ostacher & Ballon 2019; Grabitz et al. 2017 or this blog post by Prof. Dorothy Bishop http://deevybee.blogspot.com/2017/10/why-we-need-to-stop-publishing.html.