Big Names in the Field of Genetics

The study of genetics has brought great scientific advancement to the field of biology. The discovery of DNA as the building block of life in the last century gave scientists keys to unlock the mysteries of life and could potentially answer fundamental questions of our existence. The discipline of genetics was built upon the works of brilliant minds spanning many generations.

Gregor Mendel (1822-1884)

It is impossible to introduce the study of genetics without mentioning Gregor Mendel who many consider as the “Father of Genetics”.  Mendel was born in the Austrian Empire (now the Czech Republic) and studied practical and theoretical philosophy and physics in the University of Olomouc as a young man. After graduation Mendel became a priest and worked in a monastery, and it is during this time that he made his greatest discoveries and kicked start the study of genetics. Mendel conducted studies on the pea plants in the monastery’s garden and noticed interesting phenomenon between the pea plants of successive generations. He noticed that when two pea plants with different traits were cross-bred the second generation pea plants only took one of the two traits. However when the second generation plants were cross-bred the third generation plants exhibits both traits from the first generation plants and the traits existed in a fixed ration. This discovery led to Mendel’s Law of Segregation and Law of Independent Assortment which laid down groundwork for modern genetics. Gregor Mendel published these findings in 1866.

Oswald Avery (1877-1955)

By the early 1900s scientists already know that there is a link between parents and offspring and that some traits and characteristics were passed down from one generation to the next but the exact nature of such a linkage was still a mystery, this is where Oswald Avery comes in. Avery was a Canadian-born American medical researcher who was one of the pioneers in immunochemistry. In 1944 Avery studied strains of bacteria and managed to transfer disease causing material from one strain of bacteria to another previously harmless strain, the material that was moved was the nucleic acid. Avery wrote in his 1944 paper that genes and chromosomes were made of DNA and this is the hereditary material.

Erwin Chargaff (1905-2002)

Erwin Chargaff was an Austrian biochemist who later moved to the United States. Chargaff read Oswald Avery’s work on DNA and was inspired to work out the chemical composition of DNA. At the time it was hypothesized that DNA consists of four bases adenine, thymine, cytosine, and guanine. Chargaff discovered that in any species the ratio of adenine and thymine were roughly equal, so was cytosine and guanine. This was later known as Chargaff’s Rule. He concluded that there exists a complementary relationship between the pairs. Chargaff did not realize the significance of his work; it is based on his work that Francis Crick and James Watson were able to develop the double helix model for DNA.

Rosalind Franklin (1920-1958) 

Rosalind Franklin was a British biophysicist and crystallographer. In 1951 Franklin was appointed to King’s College London to work on the structure of DNA. Franklin was an expert at crystallography; she used X-Ray diffraction to photograph structure of DNA. In the 1940s and 50s Franklin along several other scientist were working on DNA at the college, including Francis Crick, James Watson, and Maurice Wilkins. An x-shaped graph of DNA taken by Franklin was shown to Crick and Watson which helped them to develop the double helix model for DNA. Rosalind Franklin is also known as the “dark lady of DNA” mainly because her work was not recognized and she died an early death from ovarian cancer due to prolonged exposure to X-ray. Maurice Wilkins later took credit for her work and shared a Nobel Prize of Physiology or Medicine with Crick and Watson in 1962. 

Francis Crick (1916-2004) and James Watson (1928- )

By the 1950s scientist were convinced that DNA is the genetic material and a race was on to build the first model of DNA. In the 1953 English molecular biologist Francis Crick and American molecular biologist/geneticist James Watson came up with the double helix model for DNA and unravelled the blueprint of life. Previous ladder model of DNA could not work in real life as it was easily broken by water, it was Watson and Crick that discovered the secret to DNA’s structure was the twist in the ladder. In a paper they published wrote: "It has not escaped our notice that the specific pairing (of purine and pyrimidine bases) that we have postulated immediately suggests a possible copying mechanism for the genetic material."  In 1962 Watson, Crick and Maurice Wilkins shared the noble prize for Physiology or Medicine.