After King George III spiraled into insanity in 1789, the study of human heredity began. Research began at England's insane asylums. This was well before DNA was discovered so to study heredity, people kept records and performed statistical calculations. Family history in madness, disability, and crime were recorded for those in asylums. Physicians considered severe mental deficits as a disease and efforts to find relatives of the sick were put into place. The number of patients institutionalized increased and discouraged the "sick" from reproducing. Ludvig Dahl published family pedigrees of mental illness in 1859 using detailed census records. Dahl helped to lay the groundwork to launch the eugenics movement by 1900. After Mendel's work with peas, eugenicists’ hoped that people inherited mental illness the same way peas inherit smooth or wrinkled skin. This idea was rejected in 1920. German researchers began to collect data on family traits of asylum patients which was later expanded by the Nazi's. This is all discussed in a book called "Genetics in the Madhouse", by Theodore M. Porter.
After coming across this article, I instantly became interested in reading this book. It's fascinating how far we have come from these times. After discovering DNA, it helped us understand genetics and heredity. The science behind genetics today is so much different from what they believed it was back then. It makes me wonder how much more we will learn in the future and if anything we believe today will be proven wrong in years to come.
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