Fig. 2

Multivariate ACE Cholesky decomposition Note: A1, A2, …, A6 represent the latent genetic factors for each of the respective traits, Whereas C1, C2, … C6 and E1, E2, …, E6 represent the latent shared and unique environmental factors influencing the six traits; The six traits are shown only for one twin, but a symmetric model applies to the co-twin. The latent genetic factors are correlated unity in monozygotic twins and 0.5 in dizygotic twins, whereas the latent shared environmental factors are correlated 1 in both types of twins and the unique environmental factors are correlated 0. Path coefficients in green (---) a11, a21, …, a66 represent loadings of the latent A components on the six traits. Path coefficents for C and E are not drawn to reduce visual clutter but blue (---) lines represent the loadings of the shared environmental factors, and red (---) lines represent the of the unique environmental factors