The sample used for the present analyses differs slightly from that which was previously reported on (Kendler et al. 2006); consequently, our precise estimates differ slightly. Heritability estimates and 95% CIs for all traits are given in Table 4. Heritability estimates for RUC were similar in the two sexes (a2 = 0.70 in males and 0.76 females). NDC was less heritable than RUC, with estimates of a2 = 0.48 in males and a2 = 0.62 in females. The remainder of the variance is attributable to non-shared environmental factors.
