DNA Timeline - Band der Zeit

Friedrich Miescher (1869) -identified "nuclein" (today's DNA) in the nuclei of white blood cells of humans -this credit tends to wrongly be given to Watson and Crick

Oswald Avery, Colin MacLeod, Maclyn McCarty (1941) -identified that DNA is the transforming principle by building on Griffith's mouse experiment -injected purified versions of DNA and protein into mice -DNA killed the mice, protein did not

James Watson & Francis Crick (1953) -developed the double helix model of DNA based on data gathered by Rosalind Franklin and Maurice Wilkins -an accurate representation of DNA in modern times

Rosalind Franklin & Maurice Wilkins (1952) -investigated the structure of DNA using X-Ray diffraction techniques -photo 51 is a famous x-ray crystallography image demonstrating a helical structure to DNA -helped Watson and Crick construct an accurate DNA model

Gregor Mendel (1866) -discovered the basic principles of genetics with his pea plant experiments -used the terms dominant and recessive to explain his experimental results -called his findings as "invisible" traits (called genes today)

Frederick Griffith (1928) -came up with the "Transforming Principle" that can change phenotype by his experiment with mice -the heat-killed virulent bacteria was able to transmit the virus into the nonvirulent bacteria

Erwin Chargaff (1950) Summarized major findings into... Chargaff's Rules: -adenine pairs with thymine -guanine pairs with cytosine -bases form weak hydrogen bonds

Alfred Hershey & Martha Chase (1952) -conclusively confirmed that DNA is the transforming factor -"Blender Experiment" -Protein(S) radioactively labeled--ends up outside in the liquid -DNA radioactively labeled--ends up inside the pellet

Phoebus Levene (1909) -discovered the basic components of nucleic acids -figured how the components fit together, including the nucleotides

Linus Pauling (1952) -came up with the triple-stranded DNA model(wrong) -induced Watson and Crick to come up with the correct model

Thomas Hunt Morgan (1908) -discovered that chromosomes are related to phenotype and also that genes are on chromosomes, by his work with fruit flies -the male fruit flies with white eyes had a specific X chromosome

William Astbury (1943) -developed X-Ray diffraction patterns -had developed an image similar to Rosalind Franklin's photo 51 before she did

Werner Arber (1962) -came up with the concept of restriction and modification enzymes, produced by bacteria, being able to defend against invading viruses -based on experiments done with lambda phages

Paul Berg (1972) -created the first recombinant DNA molecule -new discoveries in biochemistry helped with this discovery -individual genes could now be isolated and inserted into a cell

Fred Sanger (1977) -developed rapid sequencing procedure for DNA (Sanger Method) -used to determine order of bases in DNA strand

Kary Mullis (1983) -developed PCR (Polymerase Chain Reaction)--an easier method of obtaining a specific sequence of DNA -used to identify causative agents to infections -also used to screen patients for genetic diseases

Francis Collins (1989) -found the cystic fibrosis gene -used "positional cloning" -allows the ability to identify a disease gene without knowing about the functional abnormality

[CRISPR] Cas9 and PAM discovered (May 2005) -discovery made by Alexander Bolotin while studying the bacteria Streptococcus thermophilus -(Cas9-protospacer adjacent motif) a novel cas gene that encodes for a large protein predicted to have nuclease activity -(PAM) a sequence required for target recognition

Celera Organization and US Department of Energy (1990) -created the Human Genome Project to try to sequence the entire human genome -an international effort that lasted into 2003

Marshall Nirenberg & H. Gobind Khorana (1968-year of Nobel Prize) -Nirenberg discovered the first triplet/codon -codon: a sequence of three bases that codes for one of 20 amino acids -used test tube techniques for experiments -Khorana demonstrated the role of nucleotides in protein synthesis -both cracked the genetic code

George Garnow (1954) -proposed that the genetic code was determined by triplets of nucleotides -basic contribution to the modern genetic theory

History of DNA Timeline