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1858 Charles Darwin announcement of the theory of natural selection-that members of a population who are better adapted to the environment survive and pass on their traits.
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1859 Charles Darwin Published The Origin of Species.
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1869 DNA is identified by Friedrich Miescher as an acidic substance found in cell nuclei.
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1869 - Friedrich Miescher identifies an acidic substance from the nuclei of cells derived from soiled bandages. The substance was initially called 'nuclein', but would eventually be known as deoxyribonucleic acid, or DNA.
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Walter Sutton pointed out the interrelationships between cytology and Mendelism, closing the gap between cell morphology and heredity.
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Nettie Stevens Edmund Wilson found the sex chromosomes-XX determines female; XY determines male.
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1905 Some genes are linked and do not show independent assortment, as seen by Bateson and Punnett.
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Thomas Hunt Morgan had a theory of sex-linked inheritance for the first mutation discovered in the fruit fly, Found linkage.
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1928 - Frederick Griffith observes that a 'transforming factor' was responsible for changing the properties of bacteria. The experiment consisted of injecting a dead strain of disease-causing bacteria into a mice, along with a live strain that doesn't cause disease. The result was that the live strain became virulent by obtaining some component from the dead strain.
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1944 Oswald Avery
Colin MacLeod
Maclyn McCarty found that they had purified the transforming principle in Griffith's experiment and that it was DNA. -
1950 - Erwin Chargaff determines that the amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine. These four bases constitute DNA
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1951 Rosalind Franklin Obtained sharp X-ray diffraction photographs of DNA.
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Used phages in which the protein was labeled with 35S and the DNA with 32P for the final proof that DNA is the molecule of heredity.
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1958 Matthew Meselson
Frank Stahl Used isotopes of nitrogen to prove the semiconservative replication of DNA. -
1966 Marshall Nirenberg
H. Gobind Khorana Led teams that cracked the genetic code- that triplet mRNA codons specify each of the twenty amino acids. -
1972 Paul Berg
Herb Boyer Produced the first recombinant DNA molecules. -
1973 Joseph Sambrook Led the team at Cold Spring Harbor Laboratory that refined DNA electrophoresis by using agarose gel and staining with ethidium bromide.
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1975 International meeting at Asilomar, California urged the adoption of guidelines regulating recombinant DNA experimentation
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1978 Somatostatin became the first human hormone produced using recombinant DNA technology.
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1983 James Gusella Used blood samples collected by Nancy Wexler and her co-workers to demonstrate that the Huntington's disease gene is on chromosome 4.
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1985 Kary B. Mullis Published a paper describing the polymerase chain reaction (PCR), the most sensitive assay for DNA yet devised.
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1989 Francis Collins
Lap-Chee Tsui Identified the gene coding for the cystic fibrosis transmembrane conductance regulator protein (CFTR) on chromosome 7 that, when mutant, causes cystic fibrosis. -
1990 First gene replacement therapy-T cells of a four-year old girl were exposed outside of her body to retroviruses containing an RNA copy of a normal ADA gene. This allowed her immune system to begin functioning.
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Continue process human and animal cloning, research on stem cells, and genetic modification of crops.
