Investigation of many metabolic diseases is limited by the lack of availability of appropriate cell lines or animal models for these disorders. Recent work by the principal investigator's laboratory has led to the development of a retroviral vector expressing anti- sense RNA which is unusually potent at blocking gene expression. In addition, this laboratory has recently cloned a cDNA which encodes an enzyme deficient in a group of patients with an inherited metabolic myopathy, i.e. AMP deaminase deficiency. There are no cultured myocyte cell lines or animal models in which to study this inherited metabolic disease. The purpose of this proposal is to combine our expertise with retroviral anti- sense systems and knowledge of AMP deaminase expression to develop a model system for establishing phenotypes of metabolic diseases.