Table 3

Distribution of predicted mEH activity by levels of three effect modifiers mEH activitya predicted by exon 3 and exon 4 genotypes

LowMediumHigh
A. Smoking status (Excluding past smokers)
Never smoker
 Case/Control80/9753/7432/41
 ORb (95% CI)1.00 (reference)0.92 (0.57–1.49)1.13 (0.63–2.03)
Current smoker
 Case/Control27/2444/2519/8
 ORb (95% CI)1.58 (0.82–3.05)2.56 (1.38–4.74)4.27 (1.68–10.81)
Interaction, P = 0.11
B. Usual preparation of cooked meat, among never smokers who eat meat
Not well-done
 Case/Control42/4827/4211/24
 ORb (95% CI)1.00 (reference)0.81 (0.41–1.62)0.57 (0.24–1.35)
Well-done
 Case/Control36/4324/2619/13
 ORb (95% CI)1.01 (0.53–1.93)1.21 (0.58–2.53)2.47 (0.99–6.19)
Interaction, P = 0.03
C. GSTM3*A/*B Genotype among all participants
*B*B
 Case/Control142/163114/11645/55
 ORb (95% CI)1.00 (reference)1.02 (0.82–1.26)1.03 (0.67–1.58)
*A*B
 Case/Control37/4643/4935/23
 ORb (95% CI)0.86 (0.62–1.21)1.19 (0.87–1.62)1.64 (1.06–2.52)
*A*A
 Case/Control9/1518/1616/9
 ORb (95% CI)0.75 (0.38–1.47)1.64 (1.06–2.52)2.60 (1.28–5.28)
Interaction, P = 0.03
  • a Low, 0 or 1 more stable alleles (Y at exon 3 or R at exon 4), combined: HH/HH, HH/HR, or HY/HH. Medium, 2 more stable alleles: HH/RR, HY/HR, or YY/HH. High, 3 or 4 more stable alleles: HY/RR, YY/HR, or YY/RR.

  • b Adjusted for age, gender, race, date of sigmoidoscopy, and Kaiser center.