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1865 BCE
Gregor Mendel discovers the laws of inheritance.
Gregory Mendel, an Austrian monk working with pea plants, discovered the simple laws of inheritance of traits that allowed one to predict the outcome of crosses with certain traits. This is known as hybridization. -
Microbiology and the Germ Theory
Louis Pasteur describes the scientific basis for fermentation, wine making, and the brewing of beer, establishing the science of micrrobiology. He also proposed the Germ Theory, claiming that microorganisms were respondsible for infectious diseases, a radical proposal at that time. -
Beginnings of DNA
Johann Miescher found nucleic acid in white blood cells from pus in bandages. This later led scientists to believe that DNA might be the inheritable material of an organism. -
Genes and Chromosone Relations
Studying fruit flies, Thomas Hunt Morgan discovered that genes wer on chromosones. -
Transferrable Genetic Material
Fred Griffin, using mice, probed that genetic material could be moved from one strain of bacteria to another. -
Penicilin Discovery
Sir Alexander Fleming isolated penicilin from fungus. Many of his ideas are used to develop biotechnology drugs today. -
DNA Proportions and Relations
Chargaff showed that in DNA the number of units of adenine equaled those of thumine and the number of units of cytosine equaled those of guanine. -
Gene and Enzyme Hypothesis
Beadle and Tatum propose the "One gene produces one enzyme" hypothesis, using genetic analysis to analyze the results after mutating various (living) objects. -
The Double Helix
Rosalind Franklin and Maurice Wilkins established through X-ray crystallography that DNA was indeed a double helix. -
DNA: The Hereditary Material Confirmation
Using their famous "blender experiment," Hershey and Chase proved viruses replicated using DNA and confirmed the role of DNA as the hereditary material. -
DNA structure
Watson and Crick discover the structure of DNA, basing it on a spiral staircase structure and relating it to nucleotides. -
Plasmid DNA
Hayes discovered plasmid DNA, circular pieces of DNA found in bacteria. -
More Bacterial Enzymes
Arber, Nathans, and Smith discovered bacterial restriction enzymes that cut DNA. -
Codons
Khorana and NIrenberg discovered the 64 codons (the triplet code of 3 bases in DNA) that code for the 20 amino acids maknig up proteins. -
The beginning of Cloning
Cloning experiments were conducted by Boyer and Cohen. -
rDNA Guidelines
140 scientists met to draw up guidelines for work with recombinant DNA in microorganisms. Paul Berg was a key organizer. -
Synthetic Insulin
Boyer inserted a synthetic insulin gene into E. coli -
DNA Fingerprints - Restriction Fragment Length Polymorphism
Botstein found that one cold be identified by the pattern made of one's DNA through a digest by different enzymes. This DNA fingerprint was called a Restriction Fragment Length Polymorphism (RFLP). -
Vitro Fertilization
Louise Joy Brown was born, the first human baby resulting from in vitro fertilization, in which sperm and egg are joined in a petri dish. The fertilized egg is later implanted in a womb. -
The first transgenic animal
Ohio University students made the first transgenic animals. -
the first transgenic animals.
the creation of the first "transgenic animal" was accomplished by transferring a gene from one animal to the embryo of another--a mouse--in such a way that the gene would be expressed in the mouse and in its future offspring -
Technology: Polymerase Chain Reaction
Kary Mullis invents polymerase chain reactions (PCR) to amplify DNA in the labratory. -
Plants transfornations
The genetic constitution of plants can be altered in the laboratory by a process called transformation, whereby a segment of DNA (deoxyribonucleic acid) is introduced that becomes inserted in one of the plant chromosomes. Several methods to accomplish plant transformation have been devised. In all these methods, single cells are transformed and thereafter regenerated into complete, fertile plants by tissue culture procedures. -
THE HUMAN GENOME PROJECT BEGINS
In 1988, the National Research Council recommended starting a program to map the human genome. The project would develop technology for analyzing DNA; map and sequence human and other genomes – including fruit flies and mice; and other genomes – including fruit flies and mice; and study related ethical, legal, and social issues. -
The first gene therapy is approved federally and succedes
The patient was a 4-year girl suffering from an immune disorder -
Monoclonal Antibody Technology
Kohler, Milstein, and Jerne used monoclonal antibody (MAb) technology. -
Human chromosome 22 decoded!
When the sequence of human Chromosome 22 was first reported in 1999, it was the longest, continuous stretch of DNA ever decoded and assembled. Chromosome 22 was chosen as the first of the 23 human chromosomes to decode because of its relatively small size and its association with several diseases. Seeing the organization of a human chromosome for the first time at the base-pair level paved the way for the rest of the Human Genome Project. -
Genome of Drosophila melanogaster registered
Organisms such as the fruit fly, Drosophila melanogaster, have been crucial for identifying the functions of human genes. In 2000, a consortium of scientists released a substantially complete fruit fly genome sequence, obtained using several different but complementary sequencing strategies. -
First draft of the human genome released
In 2001, the Human Genome Project international consortium published a first draft and initial analysis of the human genome sequence.
For instance, the number of human genes was estimated to be about 30,000 (later revised to about 20,000). Researchers also reported that the DNA sequences of any two human individuals are 99.9 percent identical. -
Human Genome Project completion announced
VIDEO: IMPACT OF HUMAN GENOME PROJECTThe sequences produced by the Human Genome Project in 2003 covered about 99 percent of the human genome's gene-containing regions. The project was finished two-and-a-half years ahead of time, and was also significantly under budget.
The discovered genomes of organisms have been used in disease research, in the projecting new technologies for studying whole genomes
