Your Virome, 2

When viruses enter your body through eyes, nose, mouth, or broken skin, they can enter your cells, reproduce, and release millions of copies of itself. These, then, proceed to take over other cells. Sometimes viral DNA simply embeds itself in your own human DNA, where it can lie dormant or sometimes come back to life when you least want it, as occurs with recurring cold sores, shingles from a long-past chicken pox, and even some cancers, especially if your immune system is weakened. This is what can happen with Kaposi's sarcoma in immunodeficient patients infected with HIV. Sometimes, a viral code can end up in the DNA in your sperm or eggs, which then gets passed on to future generations. Viruses are champions of DNA mutation, able to carry, exchange, and modify the DNA between cells or from one species to another as when they infect bacteria. More tomorrow.