fig1

Figure 1. Bivariate Cholesky decomposition twin model for ADHD symptoms and BMI. A, C, and E represent the additive genetic, shared environmental, and unique environmental variance components, respectively. a, c, and e denote the corresponding path coefficients. ADHD symptoms and BMI are two phenotypic measures in a single twin. r_g, r_c, and r_e indicate the genetic, shared environmental, and unique environmental correlations between the two traits, respectively. For clarity, only one twin is shown. ADHD: Attention-deficit/hyperactivity disorder; BMI: body mass index.