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Gregor Mendel
Through his work with pea plants Mendel discovered many of the fundamental workings of genetics. The Punnett Square, Dominant and Recesseive traits, and genotype and phenotypes were his contributions. His work was not appreciated until rediscovered in the early 1900s. DNA was not yet known as the carrier of genetic material. -
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Discovery of DNA molecule
The genetic information molecule. -
Friedrich Miescher
Working with used hospital bandages, Miescher isolated a substance he called "nuclein" which is known today as DNA. Unfortunately, during his lifetime "nuclein" was never known to be the genetic carrying molecule - instead he thought it was a way the cell stored phosphourous. -
Hugo De Vries
De Vries performed his own experiments with breeding and came to the same conclusions that Mendel had about genetics - without knowing about Mendel. He published his paper in French without mentioning Mendel. However, later he published his findings in German and this time did mention Mendel in his writings. -
Oswald Avery
Avery built on experiments performed by Griffith using different strains of bacteria that cause pneumonia. He realized that DNA was the molecule responsible for carrying genetice information. At this time in history, however, nobody knows what DNA looks like or how it works. -
Erwin Chargaff
Chargaff discovered that the four nucleic acids that make up DNA bind in specific patterns: Adensine (A) always binds with Thymine (T) using double bonds and Cytosine (C) always binds with Guanine (G) using triple bonds. -
Rosalind Franklin
Franklin used X-ray chromatography and determined that the overall shape of the DNA molecule had to be a double helix. The her famous discovery was used later by Watson and Crick to determine the actual structure of DNA. Unfortunately, persumably due to her over-exposure to X-ray radiation, she died from cancer at age 38. When her contribution to the structure of DNA was known she had already passed away and the Nobel Prize is only given to the living, though she would have likely received it. -
Watson and Crick
Watson and Crick were the first to take into consideration all of the research that had already been done and used the results to build an actual 3-D model of the DNA molecule. They were very accurate and went on to propose other functions of DNA, both how it replicated and how it coded for proteins.
