DNA sequence The sequence of nucleotides in DNA, the molecules that control all hereditary characteristics.Gene A hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism.Gene expression The process by which a gene\u2019s coded information is converted into proteins and other molecules carrying out crucial activity within the cell. Gene expression study using microarrays The use of microarrays?high-density, 1-inch-square glass chips (similar to microchips) containing thousands of pieces of DNA?to study the activity of thousands of genes in response to many different types of stimuli. Researchers use microarray analysis to find out whether a gene is overexpressed or underexpressed in diseased cells as compared with normal conditions, how genes from different cells in a body differ in their reactions or how a gene reacts to a certain compound. Genomics The branch of genetics that studies the DNA sequences of organisms to determine what specific genes do and how we might be able to use this knowledge for therapeutic interventions.High-throughput screening The testing of potential compounds from a combinatorial library or other compound collection for biological activity in an accelerated mode (in groups of hundreds or thousands rather than 10 or 20) made possible through the use of automation and robotics.In silico Within a computer.In vitro Within an artificial environment that is outside a living organism.In vivo Within a living organism.Lead optimization The modification of a biologically active compound in vitro, in vivo and in silico to test and improve its safety and efficacy for clinical usefulness. Pharmacodynamics The chemical effects of a drug on the body.Pharmacokinetics How a drug is absorbed, distributed, metabolized and excreted in the human body.Proteomics The identification of proteins and the determination of their location, interaction, activities and ultimately their function.