Appearances Can Be Deceiving – The Problem With Genetic Knockout Mice Studies When scientists want to study the effect that a gene has on an organism, they perform what is called a “knockout” experiment. The knockout method is an experimental method, usually employed in mice, whereby the expression of a specific gene under study is blocked. The goal of this method is to learn about what effect the absence of the gene has on the animal. Due to the inevitable rise in the importance of genetic targeting in therapeutics, the knockout model has become a very important staple in studying