This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. DESCRIPTION (provided by applicant): Deletion or mutation of a single gene may result in a specific disease. Sequencing of the human genome has led to huge efforts to identify and isolate specific genes involved in the etiology of various diseases, including cancer, AIDS, diabetes, and cystic fibrosis. During the past decade, a number of gene therapies have been developed to replace defective or deleted genes with normal, functional genes. While gene therapy holds great potential for the treatment and/or cure of various diseases, it is not without risk, as demonstrated in 1999 when a teenager became the first known person in the country to die as a direct result of gene therapy.