Elaine Mardis is Associate Professor of Genetics, Department of Genetics, Washington University in St. Louis. MO, and Senior Research Scientist, Genetic Systems Division, Bio-Rad Laboratories, Hercules, CA. My research interests predominate in DNA sequencing-related technologies. As Co-Director of the Genome Sequencing Center, I help to select genomes of interest and evaluate the optimal sequencing strategy to apply to each genome. As Director of Technology Development at the GSC, I supervise a group that includes engineers and molecular biologists toward exploring and optimizing the most current technologies related to DNA sequencing, both from the standpoint of commercially available kits and instrumentation to the development of custom devices. This group has been responsible for providing many of the advances that have enabled Genome Sequencing Center production sequencing efforts to progress to higher and higher levels of throughput, efficiency and cost-savings over the years, and those efforts continue. In addition, we now are embarking on projects that center around re-sequencing, or mutational profiling, of many human genomes, namely in the context of trying to understand disease-specific somatic mutations that may predict disease onset or outcomes. This new frontier for genome sequencing of the human will continue to fuel medical discoveries for many years to come. I also have an active interest in the use of microarray technology, not only for gene expression profiling on spotted arrays using long oligonucleotide probes, but also for exploring large-scale amplification and deletion of segments of the human genome using BAC tile path arrays. These array CGH assays will provide an important adjunct to the information gained from mutational profiling of human patient samples, in helping to understand large-scale phenomena in the course of diseases, especially cancer.