Barbara McClintock was born in Hartford, Connecticut on June 16, 1902. Her research in the field of cytogenetics and certain chromosome phenomena brought her the Nobel Prize in Medicine or Physiology in 1983, “for the discovery of mobile genetic elements” – transposable elements. McClintock was the first woman to win the Nobel Prize in that category and the first American woman to win any unshared Nobel Prize.
Specifically, Barbara discovered something that was not yet a part of our textbooks, the realization that there were parts of the genome that could move or perhaps more picturesquely, “jump“. McClintock’s research and its implications was received with so much skepticism that she stopped publishing her research data in 1953.
Barbara was born Eleanor McClintock. Her parents determined when she was a young girl that Eleanor was too delicate and feminine name and chose Barbara instead. McClintock was rather solitary as a child and whilst in high school discovered her love for science. McClintock graduated early and her mother resisted furthering her education, fearing she would be unmarriageable. Her father, however, supported her to study at Cornell University’s College of Agriculture in 1919.
She received a BSc in botany in 1923 and her interest in genetics began began in 1921 when she took her first course in that field. C.B. Hutchison, a plant breeder and geneticist invited her to participate in the graduate genetics course at Cornell in 1922 McClintock later pointed to that invitation as the reason she continued in genetics. She earned her MS in 1925 and her PhD in 1927. After her PhD, she assembled a group that studied cytogenetics in maize. This was the basis of her research and life’s work which lead to her winning the Nobel Prize later in life.
We imagine a genome, ie. all of the genetic material in our cells, as something more or less static once we have a set of genes in the sex-coupling lottery. Genes are arranged linearly and should not be moved. However, McClintock found that genetic elements could “jump” – move within the genome and thus be affected. This causes neighboring genes to become active or inactive.
All her work was related to maize and the idea of exploring that hypothesis about the existence of mobile genetic elements. It was McClintock´s choice of maize as the model that was crucial for the discovery, due to the fact that very interesting things can be noticed on this plant much more easily than on any other organism.
McClintock saw that some genes could jump into a place in the genome, creating a new combination, a trait that would be expressed on the body. These mobile genetic elements will later be referred to as transposons (transponsable elements) or jumping genes.
In 1941 she accepted a position at Cold Spring Harbor Laboratory where she continued to be highly productive in her research and discoveries. She found her work a pleasure and is reported to have once said; “I can hardly wait to wake up in order to continue working.“.
After receiving the Nobel Prize, she continued her research at Cold Spring Harbor Laboratory. Barbara McClintock died of natural causes at the age of 90 in Huntington, New York on September 2, 1992. She never married or had children.
This article is part of the project “US scientist who changed the world”, grant donor US Embassy BiH.
Translated by Jonas Helgason, volunteer.
