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Gregor Mendel
Through his work on pea plants, he discovered the principles of inheritance. He concluded that genes come in pairs and are formed as specific units, one from each parent. These experiments took 8 years, and were published in 1865. -
Friedrich Miescher
He named DNA nuclein. These cells were difficult to take from the lymph glands, but they were found in great numbers in the pus from infections. He collected bandages from a nearby clinic and washed off the pus. He experimented and isolated a new molecule, nuclein, from the cell's nucleus. He determined that nuclein was made up of hydrogen, oxygen, nitrogen and phosphorus and there was an unique ratio of phosphorus to nitrogen. He later used salmon sperm instead of pus as a source. -
Frederick Griffith
Frederick Griffith was a British bacteriologist whose focus was the epidemiology and pathology of bacterial pneumonia. Griffith's famous 1928 experiment showed that bacteria can distinctly change their function and form through transformation. -
Oswald Avery
Oswald Avery and Maclyn McCarty showed that Fred Griffith’s “transforming principle" was DNA. He worked on many strains of bacteria, applying different immunological and chemical methods. In 1913, Avery published a clinical study of the tuberculosis bacterium. -
Erin Chargaff
Erwin Chargaff proposed two main rules in his lifetime which were appropriately named Chargaff's rules. The first and best known achievement was to show that in natural DNA the number of guanine units equals the number of cytosine units and the number of adenine units equals the number of thymine units. -
Rosalind Franklin
Rosalind Franklin produced the X-ray crystallography pictures of BDNA which Watson and Crick used to determine the structure of double-stranded DNA. She was able to get two sets of high-resolution photos of crystallized DNA fibers. She used two different fibers of DNA, one more highly hydrated than the other. From this she deduced the basic dimensions of DNA strands, and that the phosphates were on the outside of what was probably a helical structure. She died from cancer in 1958. -
Hershey & Chase
Alfred Hershey and Martha Chase did the Hershey-Chase blender experiment that proved phage DNA, and not protein, was the genetic material. In 1946, working with Delbrück, Hershey discovered that phage can recombine when co-infected into a bacteria host. This led to a new area of phage genetics. -
Watson & Crick
James Watson and Francis Crick came up with the structure for DNA. In 1951, Francis Crick met James Watson who was visiting Cambridge. Francis Crick, James Watson and Maurice Wilkins shared the 1962 Nobel Prize for Physiology or Medicine for solving the structure of DNA. Maurice Wilkins and Rosalind Franklin provided some of the X-ray crystallographic data. -
Venter & Collins
In the early 1990s, Venter developed the EST method of finding genes, and promoted it as cheaper and faster than the Human Genome Project that was just getting started. Collins began working on ways to search the genome for genes that cause human disease. He continued this work, which he dubbed positional cloning in 1984. In 1989, Collins had his first success with the method when he pinpointed the gene that causes cystic fibrosis.
