Famous Scientists in Genetic Research

Barbara McClintock

Barbara was an American scientist and one of the world's most distinguished cytogeneticists. Her father Thomas Henry McClintock was a physician and her mother's name was Sara Handy McClintock. She was born in Hartford, Connecticut on June 16, 1902. In 1908, Barbara's family moved to Brooklyn, New York. She did her secondary education in Erasmus Hall High School in Brooklyn. She enrolled at the Cornell University in 1919. Barbara took a course in genetics in 1921. C. B. Hutchison, a plant breeder and geneticist, conducted it. From Cornell she received the B.S. degree in 1923, the M.A. in 1925, and the Ph.D. in 1927. Barbara served as a graduate assistant in the Department of Botany from 1924 to 1927.

In 1927, she was appointed as a botany instructor. In 1930, Barbara was the first person to describe the cross-shaped interaction of homologous chromosomes during meiosis. In 1931, Barbara working with a graduate student Harriet Creighton proved the link between chromosomal crossover during meiosis and the recombination of genetic traits. She published the first genetic map for corn in 1931, showing the order of three genes on corn chromosome 9. In 1936, she accepted an Assistant Professorship in the Department of Botany at the University of Missouri. In 1938, Barbara produced a cytogenetic analysis of the centromere, describing the organization and function of the centromere.

For her groundbreaking work in the genetics of corn, she earned a place among the leaders in genetics. Barbara was elected to the prestigious National Academy of Sciences in 1944. Almost half of the human genomes are composed of transposable elements or jumping DNA. In the 1940s Dr. Barbara first recognized jumping DNA in studies of peculiar inheritance patterns found in the colors of Indian corn. Jumping DNA refers to the idea that some stretches of DNA are unstable and "transposable," meaning they can move around - on and between the chromosomes. This particular theory was confirmed in the 1980s when scientists observed jumping DNA in other genomes. Now scientists believe transposons may be linked to some genetic disorders such as leukemia, hemophilia and breast cancer. They also believe that transposons may have played significant roles in human evolution. In 1983, Barbara McClintock was awarded the Nobel Prize in Genetics for the discovery of genetic transposition. She died in Huntington, New York on September 2, 1992. To this day, her work is relevant despite the fact that much of it was completed over half a century ago, before the advent of the molecular era.

Francis Crick

Francis was born on June 8, 1916 in Northampton, England. Crick was educated at Mill Hill School, London and Northampton Grammar School. He studied physics at University College, London and obtained a Bachelor of Science degree in 1937. In 1949, Francis was working at the Cavendish Laboratory at Cambridge, investigating the structure of proteins. In 1951, James Watson, an American biologist joined the lab. Both of them formed a strong working relationship. They believed that if a three-dimensional structure of the molecule known to play a role in passing genetic information, DNA could be determined, then the way genes are passed on might also be revealed. Francis brought to the project his knowledge of X-ray diffraction, while Watson brought the knowledge of phage and bacterial genetics. They created a visual model of DNA in 1953, which over the next few years proved to fit all experimental evidence. Francis and Watson shared the Nobel Prize in physiology/medicine in 1962 'for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material'. Crick died of colon cancer in July 2004, at age 88.

Rosalind Franklin

Rosalind was born on 25 July, 1920 in Notting Hill, London. She graduated with a Ph.D. from Cambridge University in 1945. She went to work as a research associate for John Randall at King's College in London in 1951. A chemist by training, Rosalind had established herself as a world expert in the structure of graphite and other carbon compounds before she moved to London. She learned many different techniques, and how to use them to extract DNA fibers and arrange them into bundles. Eventually, using this method, Rosalind discovered the key to DNA (deoxyribonucleic acid) structure. Rosalind never did receive the due credit for her role in discovering the structure of DNA, the carrier of genetic material. Besides other notable achievements, she was the first to produce photographs that clearly illustrated DNA's helical structure and identify the location of phosphate sugars in DNA. Rosalind died of cancer on April 16, 1958.