Barbara McClintock (jun 16, 1902 – sep 2, 1992)

Description:

Barbara McClintock (June 16, 1902 – September 2, 1992), Geneticist

Life:
McClintock was born in Connecticut, USA and received her B.Sc., M.S., and Ph.D. in Botany in 1923, 1925 and 1927, respectively from Cornell University. It was during her years as an undergraduate student she took Genetics course which would influence the rest of her career.

Contributions to Science:
Long before the recognition she received for her discovery of transposable elements; McClintock’s contributions to the field of genetics were many. She was able to identify and characterize the 10 chromosomes of maize visually and morphologically; linked specific chromosome groups of traits that were inherited together, proving chromosomal crossover during meiosis and recombination of genetic traits are linked; and described the shape of chromosomes during meiosis.
McClintock’s work on transposable elements began at Cold Spring Harbor in 1941 on chromosomal instability using the differing kernel colors on a single ear of corn as her model organism. She observed that some kernel patterns appeared unstable and changed too frequently from generation to generation. She discovered some genes could “transpose” within chromosomes and were capable of switching physical traits on or off which led to her “controlling elements” theory. For the next 30 years her work was met with lots of skepticism. Finally, in 1983 Barbara McClintock won the Nobel Prize in Physiology and Medicine for the discovery of genetic transposition, becoming the first and only woman to win a Nobel Prize unshared in that category. Approximately 50% of the human genome is composed of transposon remnants, the vast majority of which still need to be characterized. Here is a link to her Nobel Lecture.

Death:
McClintock died of natural causes in Huntington, New York, on September 2, 1992 at the age of 90; she never married or had children.

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