Table 6.

Association between nicotine phenotypes and rs578776 in lifetime smokers (n = 658)

Variable	Craving			CPD			FTND
	M		SD	M		SD	M		SD
GG/GA (n = 602)a	3.8		2.5	23.9		15.9	3.5		2.5
AA (n = 56)	3.1		2.8	21.0		14.7	2.8		2.2
	b	[95% CI]	p	b	[95% CI]	p	b	[95% CI]	p
Linear regression analysisb	0.70	[0.01, 1.39]	.048	3.14	[-1.01, 7.29]	.140	0.68	[0.04, 1.35]	.045

Notes: SD = standard deviation; CI = confidence interval; craving = craving scale, lifetime, with higher values indicating greater craving (range: 0-8); CPD = cigarettes per day, during period of heaviest smoking (range: 1–80); FTND = Fagerström Test for Nicotine Dependence, lifetime (range: 0–8); b = regression coefficient; p values are reported to allow evaluation of significance, using a p value of .0068 to adjust for multiple testing.

^aGenotypes GG (n = 339) and GA (n = 263) were combined into one group because means for the phenotypes were very similar: craving, GG M = 3.83 (SD = 2.57), GA M = 3.77 (SD = 2.33); CPD, GG M = 24.34 (SD = 16.30), GA M = 23.35 (SD = 15.33); FTND, GG M = 3.53 (SD = 2.55), GA M = 3.37 (SD = 2.39).

^bAdjustedfor demographics: age, sex, ethnicity.