Ethnic-Specific Genetic Association of Variants in the Corticotropin-Releasing Hormone Receptor 1 Gene with Nicotine Dependence

Table 1

Clinical characteristics of pooled, EA, and AA samples (mean ± SD where appropriate).

Characteristic	EA	AA	Pooled populations
Number of families	200	402	602
Avg. members/family	3.17 ± 0.69	3.14 ± 0.75	3.15 ± 0.73
Number of subjects	671	1,366	2,037
% female	69.5	66.1	67.2
Age (years)	40.5 ± 15.5	39.4 ± 14.4	39.7 ± 14.8
Number of smokers	515	1,053	1,568
Years smoked	23.2 ± 13.5	20.4 ± 12.5	21.3 ± 12.9
Cigarettes smoked/day	19.5 ± 13.4	19.4 ± 13.3	19.5 ± 13.3
FTND score	6.33 ± 2.22	6.26 ± 2.15	6.29 ± 2.17
Age of smoking onset (yrs)	15.5 ± 4.4	17.3 ± 4.7	16.7 ± 4.7