The field of gene therapy has experienced steady advances in recent years, particularly around viral vector-mediated gene transfer. Retroviral vectors (RV), especially lentiviral vectors (LV), have been the conventional choice in treating inherited diseases due to their ability to stably integrate into the genome of both dividing and non-dividing target cells (by LV), such as terminally differentiated cells or quiescent stem cells. Such “gene addition” approaches allow for the persistent expression of a therapeutic transgene, which is often deficient in genetic diseases.

Recently, adeno-associated viral (AAV) vectors have gained popularity in treating some genetic diseases which are attributable to their ability to mediate stable and long-lasting expression, while largely remaining non-integrated and episomal, in non-dividing cells with specific tissue/cell tropism. Moreover, encouraging development of gene-editing systems utilizing AAV and/or LV has opened doors for novel approaches in treating genetic diseases.

The aim of this Special Issue is to provide a forum for researchers and clinicians dedicated to the investigations on the design of viral vectors, either insertional or non-integrated, with customization to particular approaches/applications, either gene addition or gene editing, for the treatment of inherited diseases. It also intends to allow new insights of potential challenges to be revealed and novel perspectives for gene therapy applications to be formulated. We welcome both original research and review articles that provide valuable insights into the design, production and application of new or existing viral vectors for their application in treating genetic diseases.

Potential topics include but are not limited to the following:

• Development of novel approach for the generation or purification of viral vectors
• Insights of new challenges in vector production
• Characterization of new application of viral vectors
• Design of viral vectors for gene therapy of genetic diseases
• Preclinical studies using viral vectors in treating genetic diseases
• Challenges of insertional gene transfer in its therapeutic application
• Insights in barrier for AAV-mediated treatment