GFAP and Huntington disease: When we collated these data into BRB Array Tools with the same filtering criteria and normalization methods as described above, surprisingly few genes (only one or two; for example upregulation of the immediate early gene egr2 in Huntington disease and CD52 and GFAP in the "stargazer" mice) were significantly regulated in common with our lysosomal storage disease mouse model (data not shown).