| Objective To analyze the survival curves of presenilin-1/presenilin-2 conditional double knockout mice (dKO mice), and provide a reference for further breeding of this strain of mice and studying the pathogenesis of Alzheimer's disease (AD). Methods dKO mice (50 females and 30 males) and wild-type controls (20 females and 20 males) were included in this study. The survival of all the mice was observed under the same condition of feeding and nutrition for two years. Life span of each mouse was calculated, survival curves were drawn, and their survival was analyzed. Results With the passing of time, the survival probability was decreased in dKO mice. The survival probabilities of female and male dKO mice were significantly worse than that of wild-type controls, respectively (P <0.001, P <0.001; P <0.001, P <0.001). No significant difference was observed between the males and females of dKO mice. Conclusions Double knockout presenilin-1 and presenilin-2 genes may shorten the life span of mice, but there is no significant gender difference between the males and females of dKO mice. |