The discovery of the complete base sequence of human genome unveils several perspectives to understand human diseases and develop new therapies. Human genome contains approximately 39,000 genes of which 26,000 code specific proteins that have been identified. There are approximately 1,500 diseases with identified molecular disturbances. Genes can modify signs and symptoms of common diseases. Thus, there are no pure monogenic diseases. Chronic diseases of adults are complex and dependent on multiple factors. Several genes that predispose to chronic degenerative diseases have been identified. This is revealing the complex nature and the interaction of these ailments with the environment. The discovery of bacterial and viral genomic sequences will allow the manufacturing of new vaccines and specific molecular antimicrobials. The new pharmacogenomics will devise treatments for each subject according to her specific genomic profile. The new applications of genomic technology is creating new paradigms in biomedical research such as functional genomics, proteonomics, epigenetic regulation. Gene diagnosis and therapy will considerably improve the future of medicine (Rev Méd Chile 2001; 129: 1329-33