CLDN5 and Machado-Joseph disease: Interestingly, in cerebellar protein extracts from MJD mice, a 100 kDa band of Claudin-5 demonstrated a 29% decrease in comparison to wild-type animals (0.77 ± 0.092 in wild-type, n = 7 versus 0.55 ± 0.032 in MJD, n = 7; unpaired t test, P = 0.05) (Fig. 5e).