The siLentMer siRNA search tool is available online at www.bio-rad.com/rnaisearch. It offers a way to review a library of validated siRNA gene targets by searching for a siRNA (by gene symbol or NCBI accession number) or browsing either the research panels they are categorized into or an alphabetical listing of the target gene symbols. Each siRNA sequence is validated to ensure its effectiveness in knocking down at least 85% of the target mRNA expression level. The siRNA duplexes are categorized into nine panels according to areas of research interest. The current research panels include angiogenesis; apoptosis; carcinogenesis; cell cycle/checkpoint; chromatin regulation; inflammation; kinases; metabolism; and toxicology/ADME. Additional panels such as stem cell research, DNA damage/repair, cardiovascular disease, and others will be added later in the year. Bio-Rad Laboratories, Inc., 510-724-7000, www.bio-rad.com.