Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online.Since the work of Charles Darwin and Gregor Mendel, scientists have striven to understand human genetic variation and its relationship to human evolution. Race and genetics is a broad multidisciplinary set of studies that attempt to use the sciences of human genetics and evolution to inform our understanding of race. Prior to the discovery of DNA as the hereditary material, scientists used blood proteins to study human genetic variation. Research by Ludwik and Hanka Herschfeld during World War I found that the frequencies of blood groups A and B differed greatly from region to region. For example, among Europeans, 15% were group B and 40% were group A. Eastern Europeans and Russians had higher frequencies of group B, with people from India having the highest proportion.