DDIT3 and amyotrophic lateral sclerosis: In DIA, CHOP protein expression was increased 1.7-fold in ALS-Tg vs. WT mice at 70d (p = 0.008), remained elevated at 90d (p = 0.001) and then increased further to 9-fold at 120–140d but due to the high degree of variability in CHOP elevation, ALS-Tg vs. WT was not significant at 120–140d (p = 0.10), there was a genotype × age interaction effect with CHOP showing an increase in ALS-Tg at 120–140d vs. 70d (p = 0.004) and 120–140d vs. 90d (p = 0.005) (Figures 6C,D).