The aim of the present study was to examine the low-dose radiation response of human normal cells using the micronucleus assay. Skin fibroblasts and keratinocytes derived from 40 cervix cancer patients were studied. After in vitro gamma irradiation with single doses ranging from 0.05 to 4 Gy, the fraction of binucleated cells with micronuclei was assessed. For each patient, the Linear-Quadratic (LQ) model and the Induced-Repair (IR) model were fitted over the whole data set (0.05-4 Gy). In conclusion, the present study showed some evidence of low-dose hypersensitivity in the fibroblasts of two patients and in the keratinocytes of four of the forty patients studied.