Table 3 Associations of genotypes with smoking initiation age (in years), daily cigarette consumption (in cigarettes per day) and FTND score as continuous traits

rs1799971

AA

25.8 ± 9.3

20.6 ± 10.3

4.1 ± 2.6

AG

25.9 ± 10.1

22.1 ± 12.0

3.5 ± 2.6

GG

27.6 ± 11.0

18.9 ± 8.9

2.7 ± 2.2

β Coefficient (se)

0.05 (1.00)

0.48 (0.84)

–0.63 (0.35)

P value^b

0.96

0.56

0.07

rs3786047

AA

26.0 ± 11.8

21.7 ± 17.6

8.0 ± 0.0

AG

24.9 ± 10.2

21.1 ± 9.8

3.9 ± 2.7

GG

26.5 ± 9.7

21.0 ± 11.4

3.6 ± 2.5

β Coefficient (se)

0.05 (1.36)

–1.11 (1.13)

0.58 (0.47)

P value^b

0.97

0.33

0.22

rs1045280

CC

23.5 ± 10.8

21.3 ± 14.4

5.0 ± 4.2

CT

24.8 ± 10.2

21.1 ± 9.8

3.9 ± 2.6

TT

26.6 ± 9.7

21.1 ± 11.4

3.6 ± 2.5

β Coefficient (se)

–0.14 (1.33)

–1.16 (1.11)

0.45 (0.45)

P value^b

0.92

0.29

0.32

rs2036657

AA

26.6 ± 9.6

21.2 ± 11.4

3.7 ± 2.6

AG

24.9 ± 10.2

20.8 ± 9.7

3.8 ± 2.6

GG

21.6 ± 10.3

21.0 ± 12.4

5.0 ± 4.2

β Coefficient (se)

–0.39 (1.31)

–1.35 (1.09)

0.32 (0.45)

P value^b

0.76

0.22

0.49

rs3852209

CC

26.4 ± 10.5

21.2 ± 11.5

3.5 ± 2.5

CT

25.5 ± 8.7

21.2 ± 10.1

4.2 ± 2.6

TT

24.9 ± 7.9

18.8 ± 9.0

2.5 ± 2.6

β Coefficient (se)

–0.60 (1.11)

–0.69 (0.93)

0.19 (0.38)

P value^b

0.59

0.46

0.62

rs2278060

AA

26.3 ± 10.6

21.4 ± 11.7

3.5 ± 2.5

AC

25.9 ± 8.6

20.9 ± 9.9

4.2 ± 2.6

CC

23.9 ± 8.4

18.9 ± 8.7

2.4 ± 2.4

β Coefficient (se)

–0.86 (1.09)

–0.70 (0.92)

0.12 (0.37)

P value^b

0.43

0.44

0.75