Table 6.
Parameter Estimates for the Bivariate ACE Models ofMastery and Alcohol Dependence
| Model | Variable | a 2 | c 2 | e 2 |
|---|---|---|---|---|
| ACE, CSL, ra, rc, re: Males | Mastery | 0.32 (0.10 to 0.39) | 0.00 (0.00 to 0.19) | 0.68 (0.61 to 0.76) |
| Alcohol dependence | 0.43 (0.03 to 0.65) | 0.12 (0.00 to 0.37) | 0.45 (0.35 to 0.58) | |
| Shared components | −0.13 (−0.24 to 0.08) | −0.01 (−0.19 to 0.07) | −0.05 (−0.12 to 0.02) | |
| ACE, CSL, ra, rc, re: Females | Mastery | 0.30 (0.04 to 0.45) | 0.04 (0.00 to 0.25) | 0.66 (0.63 to 0.77) |
| Alcohol dependence | 0.58 (0.08 to 0.81) | 0.06 (0.00 to 0.46) | 0.36 (0.19 to 0.58) | |
| Shared components | −0.07 (−0.23 to 0.17) | 0.04 (−0.14 to 0.16) | −0.12 (−0.25 to 0.00) | |
| ACE, ra, rc, re | Mastery | 0.32 (0.20 to 0.38) | 0.00 (0.00 to 0.09) | 0.67 (0.62 to 0.73) |
| Alcohol dependence | 0.55 (0.30 to 0.65) | 0.02 (0.00 to 0.20) | 0.43 (0.35 to 0.53) | |
| Shared components | −0.11 (−0.18 to −0.02) | 0.00 (−0.10 to 0.03) | −0.06 (−0.12 to −0.003) | |
| AE, ra, re | Mastery | 0.33 (0.27 to 0.38) | 0.00 | 0.67 (0.62 to 0.73) |
| Alcohol dependence | 0.56 (0.48 to 0.65) | 0.00 | 0.44 (0.35 to 0.52) | |
| Shared components | −0.12 (−0.18 to −0.06) | 0.00 | −0.06 (−0.11 to −0.002) | |
| AE, re | Mastery | 0.31 (0.26 to 0.37) | 0.00 | 0.69 (0.63 to 0.74) |
| Alcohol dependence | 0.53 (0.44 to 0.62) | 0.00 | 0.46 (0.38 to 0.56) | |
| Shared components | 0.00 | 0.00 | −0.15 (−0.19 to −0.12) | |
| AE, ra | Mastery | 0.33 (0.28 to 0.39) | 0.00 | 0.67 (0.62 to 0.72) |
| Alcohol dependence | 0.58 (0.48 to 0.66) | 0.00 | 0.42 (0.34 to 0.52) | |
| Shared components | −0.17 (−0.20 to −0.13) | 0.00 | 0.00 |
Models: CSL, common sex-limitation; A, additive genetic effect; C, environmental effect shared by co-twins; E, environmental effect not shared by cotwins; a2, proportion additive genetic variance; c2, proportion environmental variance shared by co-twins; e2, proportion environmental variance not shared by co-twins; ra, mastery/alcohol dependence genetic correlation; rc, mastery/alcohol dependence shared environmental correlation; re, mastery/alcohol dependence nonshared environmental correlation/error. Results for the best-fittingmodel are shown in bold.