Suppression subtractive hybridization (SSH) is one of the most powerful and popular PCR-based methods for isolating differentially expressed transcripts. Using a small quantity of either total RNA or poly(A)+ mRNA from each of two populations, the SSH procedure simultaneously subtracts and partially normalizes the abundance of target cDNA in the subtracted population. The clones are ligated into a vector, plated, picked, and sequenced. These genes are then available for analysis and further investigation by means of foll