A–B. Tremor onset was estimated via SHIRPA analysis on at least 8 mice per genotype per sex and time point. Tremor onset is significantly reduced in females (A) (average onset HD; Igf-1r+/−: 16.3 weeks compared HD; Igf-1r+/+: 14.1 weeks, p(Log-rank) = 0.002), but not in males (B) HD; Igf-1r+/−: 13.6 weeks compared HD; Igf-1r+/
+: 12.6 weeks, p(Log-rank) = 0.278). C–D. Time to reach end-stage (survival) of the N171-82Q HD mice is not modified by Igf-1r status. Survival was measured on at least 10 mice per sex and genotype. No significant differences were observed when comparing survival between HD; Igf-1r+/
+ and HD; Igf-1r+/− in female (C, n = 10 and 19 respectively, p (Log-rank) = 0.26) or males (D, n = 15 and 12 respectively, p(Log-rank) = 0.48), or when both sexes were combined p(Log-rank) = 0.79.