Genes are sequences of nucleic acids encoding the synthesis of proteins. If genes are altered, encoded proteins cannot properly function thus giving rise to genetic disorders. Gene therapy aims at introducing genetic material into cells to add, modify or alter genes with the aim of restoring normal protein function.

Gene therapy is becoming the future of medicine. It will provide a treatment or even a cure to many complex diseases of genetic or non-genetic origin. Current advancements have allowed gene delivery mechanisms to become more efficient and long-term gene expression to be better achieved. This will lead to an expansion in the variety of diseases that can be treated by gene therapy. Ideal candidates for gene therapy are monogenic diseases arising from one genetic mutation or dysfunction. However, the majority of diseases are more complex and involve more than one gene.

In principle, gene therapy can target somatic (body) or germ (egg and sperm) cells. In somatic gene therapy the recipient’s genome is changed, but the change is not passed on to the next generation. In the case of germ line gene therapy the newly introduced gene is passed on to the offspring.