History of human genetics

Abstract

Theories and studies in human genetics have a long history. Observations on the inheritance of physical traits in humans can even be found in ancient Greek literature. In the eighteenth and nineteenth centuries observations were published on the inheritance of numerous diseases, including empirical rules on modes of inheritance. The history of human genetics as a theory-based science began in 1865, when Mendel published his Experiments on Plant Hybrids and Galton his studies on Hereditary Talent and Character. A very important step in the development of human genetics and its application to medicine came with Garrod's demonstration of a Mendelian mode of inheritance in alkaptonuria and other inborn errors of metabolism (1902). Further milestones were Pauling's elucidation of sickle cell anemia as a molecular disease (1949), the discovery of genetic enzyme defects as the causes of metabolic disease (1950s, 1960s), the determination that there are 46 chromosomes in humans (1956), the development of prenatal diagnosis by amniocentesis (1968-1969) for the detection of chromosomal defects such as Down syndrome, and the large-scale introduction of molecular methods during the last 25 years. Concepts appropriated from human genetics have often influenced social attitudes and introduced the eugenics movement. Abuses have occurred, such as legally mandated sterilization, initially in the United States and later more extensively in Nazi Germany, where the killing of mentally impaired patients was followed by the genocide of Jews and Romani (Gypsy) people.