Human dystrophin gene transfer: production and expression of a functional recombinant DNA-based gene

The identification and cloning of the gene responsible for Duchenne muscular dystrophy (DMD) and characterization of the protein product of the gene, dystrophin, has led to major advances in diagnostic and genetic counselling procedures for this inherited disorder. Due to its high mutation rate, however, individuals affected by DMD will continue to arise in large proportion by de novo mutations, and the search for direct therapies remains a high priority. In this respect direct genetic correction of dystrophin deficiency via grafting of healthy myoblast stem cells or direct introduction of functional DNA into diseased muscle tissue have both been proposed as potential therapeutic approaches. We describe here, the first example of the engineering and cloning of a synthetic gene encoding recombinant human dystrophin and its stable transfer to and expression in mammalian cells. This DMD gene construction represents a primary step towards evaluating direct DNA-mediated gene transfer as a potential treatment for this debilitating disorder.