Deoxyribonucleic acid, or DNA, is the carrier of genetic information in living organisms. In 1953, James Watson, an American, and Francis Crick, a Briton, deduced the entire molecular structure based on Rosalind Franklin’s DNA x-ray diffraction analyses and developed the model of the DNA double helix. In 1962, Watson and Crick were awarded the Nobel Prize for Physiology and Medicine for their discoveries.