Nowadays, there are many diseases that are incurable or for which a complete remission treatment is not available. That is why gene therapy has emerged as a great alternative for these diseases. Gene therapy is a therapeutic strategy based on the genetic modification of cells, either in vivo or ex vivo, through the use of certain genetic editing methods such as programmable site-specific nucleases, like ZFNs, TALENs, CRISPR-Cas, etc., as the use of vectors responsible for transferring the gene to the target cell. Many clinical trials are underway and some have even been approved, resulting in the commercialization of gene therapy products to treat certain diseases.