Neuronal Htt knockout mice. (A) Western blots showing depletion of Htt in the brain of neuronal KO mice at 4 and 8 mo of age. See Fig. 1 for abbreviations key. (B) Survival rate of neuronal KO mice compared with the heterozygous control mice. Data were collected from the first day after tamoxifen injection. (C) Diagram showing the body weight, rotarod performance, and gripping ability at different months. Mice at different ages (2, 4, and 8 mo) were studied for 7–8 mo after tamoxifen injection (2-mo-old, n = 10; KO, male = 6 and female = 4; control, male = 4 and female = 6; 4-mo-old, n = 10; KO, male = 5 and female = 5; control, male = 5 and female = 5; 8-mo-old, KO, n = 9, male = 4, female = 5; control, n = 11, male = 6, female = 5; two-way ANOVA test, body weight, 2M control vs. 2M KO: P = 0.9945, 4M control vs. 4M KO: P = 0.9862, 8M control vs. 8M KO P = 0.9922; rotatod performance, 2M control vs. 2M KO: P = 0.9565, 4M control vs. 4M KO: P = 0.9921, 8M control vs. 8M KO P = 0.7701; gripping ability, 2M control vs. 2M KO: P = 1.0000, 4M control vs. 4M KO: P = 0.9962, 8M control vs. 8M KO P = 0.9718).