We examined genetic correlations with classical biomarkers of AGG. Higher levels of aggression have been associated with lower levels of LDL [40] and lower resting heart rate [41, 42]. We found a positive, albeit weak, rg between AGGoverall and LDL (rg = 0.15; SE = 0.07), which has an opposite sign than what was expected based on the literature [39]. More broadly, except for HDL (rg = −0.13; SE = 0.07), all measures of lipid levels returned significant positive rgs with AGGoverall, albeit weakly (rg < 0.2). No heart rate measure showed a significant genetic correlation with AGGoverall. The relationship between testosterone levels and (childhood) AGG in the literature is, at best, unclear. A positive association between AGG and testosterone is often assumed, but the relation may be more complex [43]. Both positive and negative phenotypic correlations have been found and seem context-dependent [44]. We found significant negative, rgs between AGGoverall and testosterone levels in males and females (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left| {r_g} \right|$$\end{document}rg < 0.15). These should be interpreted with some caution because
