A Hungarian noble wrote laws of heredity decades before Mendel's peas
In 1819 Imre Festetics, a nobleman in Kőszeg, published rules of inheritance that anticipated one of Mendel's laws and noticed that traits could skip generations. Mendel's own work sat unappreciated until 1900. The century that followed turned heredity from a breeder's hunch into a molecule scientists could read and copy.
People bred better crops and livestock long before anyone knew why it worked. Festetics argued that organisms inherit their characteristics rather than acquiring them, and he is sometimes called the first geneticist. Gregor Mendel, an Augustinian friar in Brno, presented his pea experiments in 1865, showing traits passed on as distinct units instead of blending. The dominant alternatives of the day were blending inheritance, implied by Darwin's Origin of Species, and the Lamarckian idea that parents pass on traits they strengthened in life, which is now known to be false.
Mendel's work was rediscovered in 1900 by Hugo de Vries and others, and William Bateson, a champion of it, coined the word genetics in 1905 from the Greek genesis, origin. Bateson drew heavily on women researchers at Newnham College, Cambridge, among them Becky Saunders. Nettie Stevens spent eleven years studying mealworms from 1900 and showed that sex is set by chromosomes, with males carrying X and Y. Thomas Hunt Morgan tied genes to chromosomes in 1911 using a white-eyed fruit fly, and his student Alfred Sturtevant showed in 1913 that genes lie in a line.
Chromosomes contain both protein and DNA, so which carried heredity? Frederick Griffith found in 1928 that dead bacteria could transform living ones, and in 1944 the Avery–MacLeod–McCarty experiment pinned transformation on DNA. The Hershey–Chase experiment of 1952 confirmed it in viruses. A year later Watson and Crick, using X-ray images from Rosalind Franklin and Maurice Wilkins, described the double helix, whose paired strands suggested how DNA copies itself.
Tools followed fast. Frederick Sanger's chain-termination method of 1977 let scientists read DNA, Kary Mullis's polymerase chain reaction of 1983 let them copy chosen stretches quickly, and the human genome was sequenced in 2003. Genes still act alongside surroundings: two genetically identical corn seeds can reach very different heights, the one grown in arid conditions only half as tall as its temperate twin.
Source: Genetics
