For HD cases, there was a significant negative correlation between the total number of cells expressing D2R and disease stage (r = 0.641, p = 0.046, Fig. 2f), with a similar trend for the number of GFAP+ astrocytes expressing D2R and HD stage (r = 0.474, p = 0.166, Fig. 2g). Here, GFAP is linked to Huntington disease.