Gene therapy applications to transfusion medicine

This chapter reviews the multiple variables to be considered when gene therapy is performed based on the type of genetic material to insert, the target cells, and the route of administration with a focus on applications of gene therapy to transfusion medicine. For safety reasons, all viral vectors for gene therapy must be incapable of replication in the human host. The major risks associated with viral vector-based gene therapy are the generation of replication-competent viruses and gene integration that could lead to the activation of oncogenes or loss of function of tumor suppressor genes. Nonviral vectors for gene therapy are also undergoing intensive investigation. Various gene-editing approaches, such as transcription activator-like effector nucleases, zinc finger nucleases, and CRISPR with CRISPR-associated 9, are described. Studies that have assessed the possible application of gene-editing techniques to hemoglobinopathies are also discussed.