Targeted gene correction: a new strategy for molecular medicine.

Advances, over the past 20 years, in the genetic manipulation of mammalian cells form the scientific basis of gene therapy. A number of strategies are presently being used to replace or augment a dysfunctional gene with a correct copy of itself. Now, a novel approach to correct the dysfunctional gene in the chromosome is being developed. Data obtained from biochemical, cell-based and animal studies suggest that the era of gene repair is dawning. It is now conceivable that inherited and non-inherited disorders might be treated with a small molecular tool designed to fix the mutation directly. Here, the conceptualization of the technique and its barriers to success are discussed.