RET and cancer: Figure 1B shows that the frequencies of immature reticulocytes (MN-RET) and mature normochromatic erythrocytes (MN-NCE) carrying micronuclei were ∼36% and ∼57% higher in the radiation-sensitive BALB/c strain than in the more radiation-resistant C57BL/6 strain [14] (p<0.0001; Table S1). These differences are at the high end of baseline variation among mouse strains [22], and are consistent with the significant associations that have been reported between blood micronuclei frequencies and cancer risks in human studies [23].