Human genetic enhancement or human genetic engineering refers to human enhancement by means of a genetic modification. This could be done in order to cure diseases (gene therapy), prevent the possibility of getting a particular disease[1] (similarly to vaccins), to improve athlete performance in sporting events (gene doping), or to change physical appearance, metabolism, and even improve physical capabilities and mental faculties such as memory and intelligence. These genetic enhancements may or may not be done in such a way that the change is heritable (which has raised concerns within the scientific community.[2][3]