Measurements of (A) TUNEL-positive thyrocytes, (B and C) fluorescence intensities of ubiquitin and 8-OHdG, and (D) number of 53BP1 foci. The thyroid glands removed in Fig. 2 (n = 3 or 4 for each group) were used for staining and measurements. The black and white bars indicate the control and Atg5^thyr-KO/KO mice, respectively. Data are means ± SE. *P < 0.05; **P < 0.01 compared with controls. M, months.