We found no significant interaction between BC and GSTP1 or GSTT1 genotypes; between SO4 and any genetic variant; for any of the genetic variants and either BC or SO4 on the change in LINE-1; or with any of the host characteristics evaluated as potential effect measure modifiers (i.e., current smoking, obesity, or use of antihypertensive medications) for either BC or SO4. Here, GSTP1 is linked to breast cancer.