 |
|
| Feb. 12, 06:17 EDT | |
| Genome map expected to speed new treatments | |
AP Science Writer |
|
|
But why these mutations prompt these diseases is imperfectly understood and patients suffer and die for reasons that still befuddle medical science. The connection between gene mutation and disease will become much clearer now, say the experts, with the mapping and sequencing of the entire human genome. They believe that new understanding eventually will lead to dramatic new treatments. ''With the anatomy of the human genome at hand, the biomedical research community is facing sweeping changes in its methods and strategies,'' write Dr. Leena Peltonen of UCLA and Dr. Victor A. McKusick at Johns Hopkins University in Baltimore. The complete genome opens up the real prospect of developing medical treatments tailor-made for individual patients, of developing drugs that attack only the disease and leave the rest of the body alone, and of predicting, perhaps at birth, which person is most likely to develop which disease and offering a way to prevent it. In the future, say Peltonen and McKusick, newborns may be screened for treatable genetic diseases and ''children at high risk of coronary artery disease can be identified and treated to prevent changes in their vascular walls during adulthood,'' thus preventing heart attacks. It may now be possible, said Barbara J. Trask of the Hutchinson Cancer Center, for medical science to pinpoint in each patient the genes that have gone awry and caused cancer and then to design a treatment specifically for that problem. ''Cancer is really a disease of the genome,'' said Trask. Some gene within the cell suddenly is changed or silenced, sending the whole cell spiraling into a pattern of uncontrolled growth and division. Having a map of the whole genome as a reference base, said Trask, ''will allow you to more rapidly find those places where the cancerous cells deviated from the reference.'' Once those changed genes are identified, scientists will be able to find what they do and why they help cancer develop and spread, she said. With the genome map, said Trask, medical science will be able to find answers about other diseases, such as why some people contracting a virus, such as HIV, rapidly become sick, while others don't. ''Why do cancer cells in some people progress and in others they do not?'' she said. ''Having the complete genome will help us figure all this out.'' Trask said cancer now is treated with ''a sledge hammer approach.'' Patients are given chemicals or radiation that attack virtually every cell in the body, not just the cancer cells. There is nausea, pain, loss of hair and general, deep exhaustion. ''Each cancer cell is special and has a different genetic reason for going awry,'' said Trask. With a genome map in hand, researchers will eventually be able to recognize the rogue genes and determine why and how they went wrong. ''We could then design treatments that specifically address that defect in the tumor and the treatments would become more targeted and less grueling for the patient,'' Trask said. Genes are not the final answer in treating disease. In most cases, a mutated or changed gene creates a predisposition to cancer or other diseases. It is thought to take an ''environmental insult'' such as smoking, to trigger the predisposition toward cancer. Genes may open the door to heart disease, but a high fat diet and a lack of exercise may also play a role. Research into the whole human genome will help find the genes that predispose for disease, and other studies will help determine the environmental influences that help give birth to the disease, Trask said. This could lead to dramatic advances in prevention. |
|