TO cure genetic diseases, scientists must first determine which gene or set of genes causes each disease. The Human Genome Project and other international efforts have completed the initial work of sequencing and mapping virtually all of the 25,000 to 35,000 genes in the human cell. This research will provide new strategies to diagnose, treat, cure, and possibly prevent human diseases.[4]
Gene therapy has had its ups and downs. Indeed, more than any other new biology technology, this one is the most erratic. It had great success with the DeSilva case, but a terrible failure with the Gelsinger case. Even worse, in 2002 a French trial to cure SCIDs, led by Dr. Alain Fischer and initially thought to be the most successful ever, suffered a setback, when two of the participants developed a vector-induced leukemia.[44]
The trouble besetting the Fischer trail doesnot mark the end of gene therapy, but it has helped scientists define the problems that must be resolved in ordr to improve the safety of this procedure: Safer vehicles must be found or designed, strategies must be developed to minimize immune rejection of the vector, and greater emphasis must be placed on risk assessment. The last of these three problem areas will be relatively easy to achieve, but the first two represent profoundly difficult biological problems that are likely to take many years to resolve.
Gene therapy's potential to revolutionize medicine in the future is exciting, and hopes are high for its role in curing and preventing childhood diseases. One day it may be possible to treat an unborn child for a genetic disease even before symptoms appear.
Scientists hope that the human genome mapping will help lead to cures for many diseases and that successful clinical trials will create new opportunities. For now, however, it's a wait-and-see situation, calling for cautious optimism.
