Table 3

ORs for breast cancer and smoking and breast cancer and radiation exposure stratified by XRCC1 codon 399 genotype among African-American participants

XRCC1 codon 399 genotype
Arg/Gln or Gln/GlnArg/Arg
Cases/ControlsOR (95% CI)aCases/ControlsOR (95% CI)aR
Never smoker52/35Referent86/126Referent
Current smoker13 /210.4 (0.2–0.9)30 /351.4 (0.8–2.4)
Former smoker24 /121.4 (0.6–3.2)48 /372.2(1.3–3.6)
Duration of smoking (yr)
 Never52/35Referent86 /126Referent
 ≤1014 /71.4(0.5–3.9)19 /241.2 (0.6–2.4)
 11–206 /80.5(0.2–1.6)19 /241.3 (0.7–2.6)
 >20917 /180.7(0.3–1.5)39 /232.9 (1.6–5.2)
P for trend test0.23<0.001
High-dose radiation to chest
 No83 /62Referent152 /183Referent
 Yes5/60.7 (0.2–2.3)12 /151.0 (0.4–2.2)
Occupational exposure to ionizing radiation
 No82 /63Referent153/190Referent
 Yes7 /51.1 (0.4–3.8)11 /81.9(0.7–4.8)
  • a Adjusted for age.