visit history of genetics History of Genetics Timeline Jo Ann Lane 1994 Woodrow Wilson Collection ----------------------------------------------------------------------- As scientists sought to understand more about the nature of inheritance of traits, hereditary processes were explained in ever increasing detail beginning at the populational level and going toward the molecular level. Keeping this fact in mind will help in understanding the timeline which follows. Year Scientist(s) Discovery Joint announcement of the theory of natural selection-that members of a 1858 Charles Darwin Alfred population who are better adapted to Russel Wallace the environment survive and pass on their traits. 1859 Charles Darwin Published The Origin of Species. Published the results of his 1866 Gregor Mendel investigations of the inheritance of "factors" in pea plants. Carl Correns Hugo de Mendel's principles were 1900 Vries Erich von independently discovered and Tschermak verified, marking the beginning of modern genetics. Pointed out the interrelationships 1902 Walter Sutton between cytology and Mendelism, closing the gap between cell morphology and heredity. Independently described the behavior 1905 Nettie Stevens Edmund of sex chromosomes-XX determines Wilson female; XY determines male. Proposed that some human diseases 1908 Archibald Garrod are due to "inborn errors of metabolism" that result from the lack of a specific enzyme. Proposed a theory of sex-linked inheritance for the first mutation 1910 Thomas Hunt Morgan discovered in the fruit fly, Drosophila, white eye. This was followed by the gene theory, including the principle of linkage. 1927 Hermann J. Muller Used x-rays to cause artificial gene mutations in Drosophila. Proposed that some unknown 1928 Fred Griffith "principle" had transformed the harmless R strain of Diplococcus to the virulent S strain. 1931 Harriet B. Creighton Demonstrated the cytological proof Barbara McClintock for crossing-over in maize. Irradiated the red bread mold, 1941 George Beadle Neurospora, and proved that the gene Edward Tatum produces its effect by regulating particular enzymes. Oswald Avery Reported that they had purified the 1944 Colin MacLeod transforming principle in Griffith's Maclyn McCarty experiment and that it was DNA. Organized a phage course at Cold Spring Harbor Laboratory which was 1945 Max Delbruck taught for 26 consecutive years. This course was the training ground of the first two generations of molecular biologists late Developed the hypothesis of 1940s Barbara McClintock transposable elements to explain color variations in corn. Discovered a one-to-one ratio of 1950 Erwin Chargaff adenine to thymine and guanine to cytosine in DNA samples from a variety of organisms. 1951 Rosalind Franklin Obtained sharp X-ray diffraction photographs of DNA. Used phages in which the protein was 1952 Martha Chase labeled with 35S and the DNA with Alfred Hershey 32P for the final proof that DNA is the molecule of heredity. 1953 Francis Crick Solved the three-dimensional James Watson structure of the DNA molecule. Used isotopes of nitrogen to prove 1958 Matthew Meselson the semiconservative replication of Frank Stahl DNA. Purified DNA polymerase I from E. 1958 Arthur Kornberg coli, the first enzyme that made DNA in a test tube. Led teams that cracked the genetic 1966 Marshall Nirenberg code- that triplet mRNA codons H. Gobind Khorana specify each of the twenty amino acids. Isolated the first restriction 1970 Hamilton Smith enzyme, HindII, that could cut DNA Kent Wilcox molecules within specific recognition sites. 1972 Paul Berg Produced the first recombinant DNA Herb Boyer molecules. Led the team at Cold Spring Harbor 1973 Joseph Sambrook Laboratory that refined DNA electrophoresis by using agarose gel and staining with ethidium bromide. Showed that a recombinant DNA 1973 Annie Chang molecule can be maintained and Stanley Cohen replicated in E. coli. International meeting at Asilomar, 1975 California urged the adoption of guidelines regulating recombinant DNA experimentation. 1977 Fred Sanger Developed the chain termination (dideoxy) method for sequencing DNA. The first genetic engineering 1977 company (Genentech) is founded, using recombinant DNA methods to make medically important drugs. Somatostatin became the first human 1978 hormone produced using recombinant DNA technology. Three independent research teams 1981 announced the discovery of human oncogenes (cancer genes). Used blood samples collected by 1983 James Gusella Nancy Wexler and her co-workers to demonstrate that the Huntington's disease gene is on chromosome 4. Published a paper describing the 1985 Kary B. Mullis polymerase chain reaction (PCR), the most sensitive assay for DNA yet devised. The Human Genome Project began with 1988 the goal of determining the entire sequence of DNA composing human chromosomes. Coined the term DNA fingerprinting 1989 Alec Jeffreys and was the first to use DNA polymorphisms in paternity, immigration, and murder cases. Identified the gene coding for the cystic fibrosis transmembrane 1989 Francis Collins conductance regulator protein (CFTR) Lap-Chee Tsui on chromosome 7 that, when mutant, causes cystic fibrosis. First gene replacement therapy-T cells of a four-year old girl were exposed outside of her body to 1990 retroviruses containing an RNA copy of a normal ADA gene. This allowed her immune system to begin functioning. FlavrSavr tomatoes, genetically 1993 engineered for longer shelf life, were marketed. -----------------------------------------------------------------------