Gene therapy has become a revolution and its breakthrough is a corner stone in modern science. This treatment has rising advantages with limited negative aspects. Gene therapy is a therapeutic method in which, transfer of DNA to an individual to manipulate a defective gene is performed and to mitigate a disease which is not responding to pharmacological therapy. The gene therapy strategies are divided into two main categories such as direct in-vivo gene delivery of manipulated viral vector vehicle into the host and ex-vivo genetically engineered stem cells. In this review, we tried to cover all aspects of gene therapy studies; starting with the concept of gene, its treatment, gene delivery system and types, clinical trial either by vitro or In-Vivo -Clinical Trials and Clinical Intoxication of Gene Therapy. Therefore, the promise of successful treatment with gene therapy could positively affect millions of lives. The main aim of this review is to address the principles of gene therapy, various methods involved in the gene therapy, clinical applications and its merits and demerits

doi.org/10.1016/j.gene.2020.145246 - 2022