Table 5.

Extent of additive genetic (below diagonal) and non-shared environmental (above diagonal) overlap across positive and negative subjective initial reactions to cannabis and tobacco in European-American female twins.

	Tobacco +	Tobacco −	Cannabis +	Cannabis −
Tobacco +	1.0	0.00	0.08 [-0.01 to 0.17]	0.21 [0.12–0.28]
Tobacco −	0.36 [0.23–0.49]	1.0	−0.16 [-0.25 to −0.07]	0.36 [0.30–0.42]
Cannabis +	0.58 [0.35–0.85]	−0.07 [-0.32 to 0.20]	1.0	0.12 [0.05–0.19]
Cannabis −	0.52 [0.32–0.72]	0.18 [0.09–0.30]	0.30 [0.15–0.50]	1.0