MAOA-LPR genotype moderated the impact of stressful life events experienced between ages 6 months to 3 ½ years on hyperactivity in girls at 4 years (β = −0.22; 95% CI: −0.35 to −0.09; p for interaction = 0.001) and at 7 years (β = −0.18; 95% CI: −0.31 to −0.05; p for interaction = 0.009). The low activity allele was associated with increased hyperactivity in girls exposed to high stress (Figure 1).
