Each of us has a biological identity. Many consider this simply a consequence of our DNA, our genes. Our DNA demonstrates our relatedness to each other, but if we understand the way in which it is shuffled in our offspring and how it is regulated throughout our lives, then we can see the biological reason for our own identity. As we begin to ask deep questions about our lives as socially organized beings, are three-parent babies really that bad? Should we eradicate all humans who may carry incurable genetic diseases? If my DNA is found at a crime scene, was I really there? This chapter will seek to use these questions to develop a broader understanding of biological identity.