Leading academic and industrial investigators surveys the world of microarray technology, describing in step-by-step detail diverse DNA and protein assays in clinical laboratories using state-of-the-art technologies. The advanced tools and methods described are designed for mRNA expression analysis, SNP analysis, identification, and quantification of proteins, and for studies of protein-protein interactions. The protocols follow the successful Methods in Molecular Biologya''¢ series format, each offering step-by-step laboratory instructions, an introduction outlining the principle behind the technique, lists of the necessary equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.