Genetic differences in transcript responses to low-dose ionizing radiation identify tissue functions associated with breast cancer susceptibility.

This study investigates three radiation exposure scenarios in BALB/c and C57BL/6 mice: (1) low dose (LD) group -- four weekly doses of 7.5 cGy, (2) high dose (HD) group -- four weekly doses of 1.8 Gy, (3) unexposed group -- four weekly sham exposures. We then used comparative expression profiles of the mouse mammary gland and cardiac blood to build a model of candidate tissue functions associated with LD cancer susceptibility in these strains and murine and human knowledgebases to characterize these tissue functions and their relevance to breast cancer. All samples were assessed on Affymetrix MOE 430 A arrays (HT_MG-430A; GPL8759). Mammary gland tissues: 43 samples (2 strains, 3 treatments, 2 timepoints, 2-4 replicates). For Cardiac blood tissue: 8 samples (2 strains, 4 replicates)