The Practical Applications of
Human Genetic Technology
Biological knowledge affects health once it is translated into practical tools. The knowledge obtained from the Human Genome Project will have tremendous implications for the future of medicine as we develop genetic technologies that enable us to prevent and treat a wide range of clinical conditions.
It is important to discuss briefly what we mean by "genetic technology" In the near future, much of the technology emerging from the Human Genome Project will focus directly on the genes themselves. A technique that uses short strands of genetic material, called DNA probes, will be used to detect normal and abnormal genes for diagnostic and screening purposes, and gene therapy will be used to transfer genes into cells to repair, alter, or enhance their function. But as our knowledge becomes more sophisticated, diagnostic techniques may focus on detecting the presence or absence of gene products, such as proteins, rather than the gene itself, and therapies for genetic disorders will be based on a manipulation of a cell's structure or metabolic functions rather than its DNA. Of course, this is exactly what medicine is doing now for many genetic diseases, although not necessarily very effectively. We diagnose sickle cell anemia by analyzing hemoglobin rather than DNA, and we treat cystic fibrosis with antibiotics and pancreatic enzymes rather than with altered DNA (although gene therapy trials are underway for CF). The point is that genetic or DNA-based technology is not the ultimate goal of genetic research. The goal is an understanding of biology that will yield DNA-based tools, as well as tools based on other aspects of the life process. It is likely that the first generation of genetic technologies will be DNA-based. But by the term "genetic technologies," we also mean to refer to later, more powerful interventions that stem indirectly from our new understanding of the human genome.
Genetic technology in humans will yield three major practical applications: screening and diagnostic technology, gene therapy, and genetic enhancement. The development of a genetic map will make