The human genome project and clinical medicine.

Genetic research has already begun to pay clinical dividends, as investigators have successfully isolated disease genes, including those responsible for Duchenne muscular dystrophy, cystic fibrosis, and the fragile X syndrome. This last disorder appears to be associated with the progressive amplification of a short, repeated DNA sequence, a mechanism that may also occur at other cytogenetically fragile sites and in other genetic disorders or neoplasias. This article reviews genetic mapping techniques being used by the Human Genome Project, methods for identifying disease genes, and clinical applications. It also includes discussions of mutation detection, diagnosis, and gene therapy.