Interaction between cytochrome P450 2A6 and Catechol-O-Methyltransferase genes and their association with smoking risk in young men

Table 2 Odds ratios for the effects of CYP2A6 and COMT polymorphisms on smoking status

Genotypes interaction	Current smokers N = 261	Never smokers N = 219	OR (95% CI)	P^a
Model 1
CYP2A6
Wild type	63	46	1.0
High activity	144	119	0.88 (0.56–1.39)	0.591
Low activity	54	54	0.73 (0.43–1.25)	0.249
Model 2
COMT
COMT rs4680
Wild type	147	113	1.0
Variant	114	106	0.83 (0.58–1.19)	0.301
COMT rs165599
Wild type	61	45	1.0
Variant	200	174	0.85 (0.55–1.31)	0.458
Model 3
COMT rs4680/COMT rs165599
Wild type/wild type	27	13	1.0
Wild type/variant	120	100	0.58 (0.28–1.18)	0.128
Variant/wild type	34	32	0.51 (0.23–1.16)	0.107
Variant/variant	80	74	0.52 (0.25–1.08)	0.078
Model 4
COMT rs4680 wild type
CYP2A6 wild type	35	25	1.0
CYP2A6 high activity	76	65	0.84 (0.45–1.54)	0.563
CYP2A6 low activity	36	23	1.12 (0.54–2.33)	0.765
Model 5
COMT rs4680 variant
CYP2A6 wild type	28	21	1.0
CYP2A6 high activity	68	54	0.94 (0.48–1.84)	0.867
CYP2A6 low activity	18	31	0.44 (0.19–0.98)	0.043
Model 6
COMT rs165599 wild type
CYP2A6 wild type	15	8	1.0
CYP2A6 high activity	33	30	0.59 (0.22–1.58)	0.289
CYP2A6 low activity	13	7	0.99 (0.28–3.48)	0.988
Model 7
COMT rs165599 variant
CYP2A6 wild type	48	38	1.0
CYP2A6 high activity	111	89	0.99 (0.59–1.64)	0.961
CYP2A6 low activity	41	47	0.69 (0.38–1.26)	0.224

^aMantel–Haenszel Chi square test
The genotypes of (1) CYP2A6: wild-type (*1A/*1A), high activity (*1A/*1B and *1B/*1B), low activity (*1A/*4C, *1B/*4C, and *4C/*4C); (2) COMT rs4680: wild-type (G/G), variant (G/A and A/A); and (3) COMT rs165599: wild-type (A/A), variant (A/G and G/G)

ISSN: 1744-9081