****IMPORTANT****:if libraries: library(ArrayExpress), library(hgu133a.db), library(limma) are not installed in the local R installation, then they need to be installed before running this workflow. Original data come from Hodges et. al 2006 "Regional and cellular gene expression changes in human Huntington’s disease brain" This workflow loads the two necessary files (gene expression data & phenotype data), and creates the expression set object to be used by the R package limma, to test for ...