Genomics and the Human Genome Project are creating important changes in medical care and radiologic practice. Readers of this article will: Recall that deoxyribonucleic acid (DNA) is the information-containing molecule. Understand the relationship between DNA and protein synthesis. Learn that changes in DNA-encoded proteins produce pathogenesis. Distinguish between genomics and proteomics. Describe the Human Genome Project. Define and give examples of molecular medicine and its imaging applications. Discuss how genomics, genetic engineering and the Human Genome Project may influence radiologic practice.