The understanding and research of many diseases is currently based on genetic findings. The idea of being able to master diseases through controlled genetic manipulations is now a step closer to reality thanks to viral vectors. Viral vectors are specifically modified viral particles that are used as "transporters" to smuggle genetic material into target cells. They can be used to research a wide variety of diseases as they allow the scientist to investigate and manipulate the functionality of genes. The overexpression, correction, blockade or even removal of selected genes are just some of the possibilities enabled by these vectors. To select a suitable viral vector in its specific field of application, certain factors need to be considered, such as the transmission route, cell tropism, the size of the transgene or possible side-effects.