Abstract
Previous research points to the heritability of risk-taking behavior. However, evidence on how genetic dispositions are translated into risky behavior is scarce. Here, we report a genetically-informed neuroimaging study of real-world risky behavior in a large European sample (N=12,675). We found negative associations between risky behavior and grey matter volume (GMV) in distinct brain regions, including amygdala, ventral striatum, hypothalamus and dorsolateral prefrontal cortex (dlPFC). Polygenic risk scores for risky behaviors, derived from a genome-wide association study in an independent sample (N=297,025), were inversely associated with GMV in dlPFC, putamen, and hypothalamus. This relation mediated ∼2.2% of the association between genes and behavior. Our results highlight distinct heritable neuroanatomical features as manifestations of the genetic propensity for risk taking.
One Sentence Summary Risky behavior and its genetic associations are linked to lower grey matter volume in distinct brain regions.
Footnotes
↵1 Self-reports of the number of sexual partners have been implicated in risky behaviors related to alcohol abuse (i.e., binge drinking) and unprotected sex, specifically in young adults (8), irrespective of gender or sexual orientation.
↵2 In Karlsson Linnér et al. (2019), the phenotype ‘risky behavior’ as defined here was referred to as the ‘first PC of the four risky behaviors’.
↵3 These IDPs were extracted using parcellations from the Harvard-Oxford cortical and subcortical atlases and Diedrichsen cerebellar atlas, and consists of all the GMV IDPs derived by the UKB as for August 2019.