If you share most of the same genetic material, what makes you so different from your siblings? How much are the things you choose to do everyday--what you eat, how you vote, who you love--determined by your genes, and how much is your own free will? Using fascinating case studies of identical twins, leading geneticist Tim Spector explains how even real-life "clones" with the same upbringing turn out in reality to be very different. Drawing on his own cutting-edge research in genetics, Spector show us that nothing is completely hard-wired or pre-ordained. Challenging, enlightening and entertaining, Identically Different explores topics as varied as why the Dutch have become the tallest nation in the world, why autism is more heritable than breast cancer, and what could cause a healthy man to have a heart attack within weeks of his overweight, heavy smoking identical twin. Spector's probing and thoughtful study helps us to understand what makes each of us so unique.