Barbara McClintock found jumping genes, then stopped publishing because nobody believed her
In the 1940s and 1950s Barbara McClintock discovered that pieces of DNA can move around a genome, switching traits on and off. Colleagues were so sceptical that in 1953 she quit publishing her data. Decades later others confirmed it, and she won an unshared Nobel Prize in 1983.
McClintock was born Eleanor in Hartford, Connecticut, in 1902; her parents decided the name was too delicate and renamed her Barbara. She grew up largely in Brooklyn, independent from a young age, a trait she later called her capacity to be alone. Her mother opposed college, fearing it would make her unmarriageable, and only her father's last-minute support let her enrol at Cornell's College of Agriculture in 1919. There she played jazz, took her first genetics course in 1921, and earned a botany PhD in 1927.
At Cornell she built a group studying maize cytogenetics, the link between visible chromosomes and inherited traits, whose members included future Nobel laureate George Beadle and Harriet Creighton. Using carmine stain she was the first to show the shapes of all 10 maize chromosomes. In 1930 she first described the cross-shaped pairing of matching chromosomes during meiosis, and in 1931 she and Creighton proved that physical crossing-over of chromosomes goes hand in hand with the recombination of traits, something until then only hypothesised. She also demonstrated the importance of telomeres and centromeres.
Fellowships took her to Missouri, Caltech and, in 1933, to Germany, which she left early amid mounting tension. At Missouri, working with X-rays, she watched irradiated chromosomes break and fuse. Her later maize work revealed transposons, genetic elements that change position and control whether genes are expressed from one generation to the next.
The implications were radical, and scepticism was intense. Her work was widely grasped only in the 1960s and 1970s, once others had verified the mechanisms she described. Her 1983 Nobel Prize in Physiology or Medicine for genetic transposition makes her, as of 2025, the only woman to receive an unshared prize in that category. In later years she also studied the genetics and ethnobotany of South American maize varieties. She died in 1992.
Source: Barbara McClintock
