Genes are complex systems that determine a person’s eye color, hair color and susceptibility to certain diseases such as heart disease. What are the driving factors in genetic expression? That’s one question Karissa Sanbonmatsu, a structural biologist at Los Alamos National Laboratory, is trying to answer by creating 3D simulations of genes. She explains how visual simulations at the molecular level will lead to a better understanding of genetic expression and better medical treatments.