Gene expression within the body is controlled by the cells, which determine when a specific gene should or should not be expressed. Influenza (the flu) is caused by a virus that attacks the respiratory system. Which type of gene is likely to be widely expressed in the body of someone who contracts the influenza virus? The gene that controls production of stem cells. The gene that controls production of skin cells. The gene that controls production of red blood cells. The gene that controls production of white blood cells.