Table 2.

Odds ratios for breast cancer and total PCBs in relation to CYP1A1 M2 genotypes in white women

Total PCBsa	CYP1A1 M2 genotype	All participants		Premenopausal		Postmenopausal
		Patients/controls	OR (95% CI)b	Patients/controls	OR (95% CI)b	Patients/controls	OR (95% CI)b
<0.349	Non-M2	210/158	Referent	141/98	Referent	69/60	Referent
≥0.349	Non-M2	138/166	0.7 (0.5–1.0)	45/51	0.6 (0.4–1.0)	93/115	0.8 (0.5–1.2)
<0.349	Any M2	11/20	0.4 (0.2–0.8)	8/16	0.3 (0.1–0.8)	3/4	0.7 (0.1–3.1)
≥0.349	Any M2	15/14	0.9 (0.4–1.9)	6/2	2.1 (0.4–10.6)	9/12	0.7 (0.3–1.9)
ICR (95% CI)			0.8 (0.1, 1.6)		2.1 (-1.3,5.5)		0.3 (-0.9,1.5)

^aLipid-adjusted total imputed PCBs (ng/ml).

^bOdds ratios adjusted for age and sampling fractions.

Any M1, M1/M1 or M1/non-M1; CI, confidence interval; ICR, interaction contrast ratio; non-M1, non-M1/non-M1.