FIG. 5.
Effect of hydroxyurea, aphidicolin, and gamma irradiation on the rate of CAG repeat contractions in APRT(CAG)61 and APRT(CAG)95 cell lines. Cells were treated with hydroxyurea (HU), aphidicolin (APC), and gamma irradiation (γ) as described in Materials and Methods and were incubated in the presence of APRT+ selection, and the number of APRT+ clones was scored. Approximately 107 cells were used for each treatment. All the treatments were repeated at least three times, and error bars represent the standard deviation.