Table 2.

Genetic correlations (${\text{r}}_{\text{G}}$) between any two (trait1, trait2) of the five smoking and alcohol-related discovery phenotypes that were meta-analysed by genome-wide association studies.

Trait1	Trait2	${\text{r}}_{\text{G}}$	SE	p value
AI	CPD	−0.381	0.037	< 0.001
AI	DPW	−0.15	0.031	< 0.001
AI	SC	−0.294	0.041	< 0.001
AI	SI	−0.685	0.024	< 0.001
CPD	DPW	0.084	0.028	0.0030
CPD	SC	0.426	0.033	< 0.001
CPD	SI	0.28	0.033	< 0.001
DPW	SC	0.104	0.033	0.0016
DPW	SI	0.403	0.018	< 0.001
SC	SI	0.39	0.029	< 0.001

The ${\text{r}}_{\text{G}}$, standard errors (SE) and p values were estimated by cross-trait LD score regression. These five phenotypes are smoking initiation (SI, binary), age at starting regular smoking (AI, continuous), cigarettes per day (CPD, continuous), smoking cessation (SC, binary), and drinks per week (DPW, continuous).