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Natural Selection
Charles Darwin wrote “On the Origin of Species by Means of
Natural Selection, or the Preservation of Favored Races in the
Struggle for Life.” -
gregor mendal
Gregor Mendel published the results of his investigations of the inheritance of "factors" in pea plants. Gregor Mendel is usually considered to be the founder of modern genetics. -
DNA is identified
DNA (first called "nuclein") is identified by Friedrich Miescher as an acidic substance found in cell nuclei -
Mitosis
Walter Flemming describes chromosome behavior during
animal cell division. He stains chromosomes to observe them
clearly and describes the whole process of mitosis in 1882. -
the rediscovery of medel's experiments
Mendel's experiments from 1866 are "rediscovered" and confirmed by three separate researchers. A British man (William Bateson) soon translates Mendel's paper into English and champions the study of heredity in England -
The chromosome theory of heredity
The chromosome theory of heredity is proposed by Sutton. Boveri recognizes that individual chromosomes are different from one another, but he doesn't make a connection to Mendelian principles. Nevertheless, Boveri is given co-credit by friend E.B. Wilson for proposing the chromosome theory of inheritance -
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chromosome theory confirmed
The chromosome theory of heredity is confirmed in studies of fly eye color inheritance by T.H. Morgan and colleagues. -
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The eugenics movement
The eugenics movement is popular, fueling racist sentiment and leading to involuntary sterilization laws -
Chromosomes Carry Genes
Thomas Hunt Morgan and his students study fruit fly
chromosomes. They show that chromosomes carry genes, and
also discover genetic linkage. -
Fred Griffith
Some component of heat-killed virulent bacteria can "transform" a non-virulent strain to become virulent, as shown by Fred Griffith. -
one gene, on protein
One gene encodes one protein, as described by Beadle and Tatum -
Erwin Chargaff
In DNA, there are equal amounts of A and T, and equal amounts of C and G, as shown by Erwin Chargaff. However, the A+T to C+G ratio can differ between organisms -
Genes Are Made of DNA
Alfred Hershey and Martha Chase show that only the DNA of a
virus needs to enter a bacterium to infect it, providing strong
support for the idea that genes are made of DNA -
Watson and Crick
DNA is in the shape of a double helix with antiparallel nucleotide chains and specific base pairing. This was deduced by Watson and Crick, who used Rosalind Franklin's data provided by Maurice Wilkins. -
Arthur Kornberg
Arthur Kornberg discovered DNA polymerase enzymes. -
Genetic Code Cracked
Marshall Nirenberg and others figure out the genetic code
that allows nucleic acids with their 4 letter alphabet to
determine the order of 20 kinds of amino acids in proteins. -
First Disease Gene Mapped
A genetic marker for Huntington’s disease is found on
chromosome 4 -
First Time a Disease Gene is Positionally Cloned
A method for finding a gene without the knowledge of the
protein it encodes is developed. So called, positional cloning
can help in understanding inherited disease, such as muscular
dystrophy. -
Microsatellites Are New Genetic Markers
Repetitive DNA sequences called microsatellites are used as
genetic landmarks to distinguish between people. Another type
of marker, sequence–tagged sites, are unique stretches of DNA
that can be used to make physical maps of human
chromosomes. -
First cloned mammel
After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs, deer, horses and bulls. The attempt to clone argali (mountain sheep) did not produce viable embryos -
Jesse Gelsinger
Researchers at the Institute for Human Gene Therapy at the University of Pennsylvania accidentally kill Jesse Gelsinger during a clinical trial of a gene therapy technique, leading the FDA to halt further gene therapy trials at the Institute -
artificial polio virus
First virus produced 'from scratch', an artificial polio virus that paralyzes and kills mice.
