Over the past three decades, gene therapy has been making considerable progress as an alternative
strategy in the treatment of many diseases. Since 2009, several studies have been reported in
humans on the successful treatment of various diseases. Animal models mimicking human disease
conditions are very essential at the preclinical stage before embarking on a clinical trial. In gene therapy,
for instance, they are useful in the assessment of variables related to the use of viral vectors such as safety, efficacy,
dosage and localization of transgene expression. However, choosing a suitable disease-specific model is of paramount importance
for successful clinical translation. This review focuses on the animal models that are most commonly used in
gene therapy studies, such as murine, canine, non-human primates, rabbits, porcine, and a more recently developed humanized
mice. Though small and large animals both have their own pros and cons as disease-specific models, the choice
is made largely based on the type and length of study performed. While small animals with a shorter life span could be
well-suited for degenerative/aging studies, large animals with longer life span could suit longitudinal studies and also help
with dosage adjustments to maximize therapeutic benefit. Recently, humanized mice or mouse-human chimaeras have
gained interest in the study of human tissues or cells, thereby providing a more reliable understanding of therapeutic interventions.
Thus, animal models are of great importance with regard to testing new vector technologies in vivo for assessing
safety and efficacy prior to a gene therapy clinical trial.