 Hi, I'm Camry Pirro from Ms. Pena Science Class in Kirtland, Mexico. I have a question for you. Is there any way to create a unicorn by crossing DNA? Hi, I'm Dr. Sara Thornton from the biology department here at MIT, and I'm here today to answer your question, how do you make a unicorn? So, I've heard an important part of being a unicorn is being magic, and I can't really help you with that part, but let's talk about making a horse with a horn in the middle of its head. That's something that scientists are well on the path of being able to do. So, you may have heard about the human genome. This is basically the set of instructions for making you, you. Each of your cells in your body has a copy of your genome, and it's made of DNA and it has about 25,000 genes in it. You started as one cell, and following the instructions in your genome, you became a human with trillions of cells all in the right places. So, for example, you have kidney cells in your kidney, and liver cells in your liver, and skin cells in your skin. In fact, humans aren't the only ones to have genomes. All living organisms have genomes. So, ants have genomes, and bacteria have genomes, and tomatoes have genomes, and horses have genomes. When we understand these genomes, we can edit the genome and then change the characteristics of the organism. For example, we could take one gene from a flower that makes that flower blue, insert it into the tomato genome, and make a blue tomato, and that's pretty cool. So, what do we actually need to know to make a horse with a horn in the middle of its head, or a unicorn? Well, we want to know what parts of the genome will actually make a horn in the middle of the head. So, maybe we could take a look at the rhinoceros genome, because rhinos have a horn in the middle of their head. We actually know what the sequence of the rhino genome is, which means we know what it looks like, but we don't understand the whole thing yet. And it's kind of like trying to read a book that's in a language that you don't know. And there's a lot of scientists that are working every day on the problem of figuring out how to decode genomes. So, once we figure out what part of the rhino genome codes for one horn in the middle of the head, and it develops properly at the right time, we could take those pieces from the rhino genome, insert them into the horse genome. And if we do this in the right kind of horse cell, we could implant that cell into a mother horse and let it multiply, divide, and eventually become a baby unicorn. Magic not included.