REPAIRING GENES by taking advantage of chromosomal recombination is emerging as a promising new approach to gene therapy, according to speakers at the recent 16th International Congress of Genetics in Toronto.
Although gene therapy was once thought to be nearing clinical trials, numerous technical problems have kept it in the laboratory. One principal stumbling block has been an inability to get inserted genes to express proteins at useful levels in animal models.
The difficulty, many investigators say, arises from the vehicles used to transport genes into the cell. The most widely used vehicles, modified retroviruses, are essentially unguided missiles that deposit their cargo randomly about the genome. The transported genes, out of their customary positions, are usually only temporarily activated, if at all.
One solution may be to repair the defective gene in place, suggests Paul Berg, PhD, director of the Beckman Center for Molecular and Genetic Medicine, Stanford (Calif)