By the early 1980s, geneticist Barbara McClintock's once-controversial theory of transposable genetic elements, or "jumping genes," discovered decades earlier through painstaking maize studies, was being confirmed across many organisms including bacteria and fruit flies. Her insight that genes could move within a genome and regulate other genes reshaped molecular biology. The following year, in 1983, she received the Nobel Prize in Physiology or Medicine, decades after her original discovery.
Barbara McClintock spent the 1940s and 1950s doing something that seemed almost like alchemy to her contemporaries: reading the genetic history of corn kernels by studying the patterns of color on their husks. Working largely alone at Cold Spring Harbor Laboratory, she deduced that certain genetic elements could physically move from one location on a chromosome to another, switching neighboring genes on or off in the process.
When she presented her transposition theory in 1951, the reaction from the genetics establishment was polite bewilderment at best, outright dismissal at worst. Molecular biology in that era was becoming obsessed with the elegant, static logic of DNA's double helix, and McClintock's discovery of genomic instability and movement didn't fit the prevailing narrative. She reportedly stopped presenting her data at conferences for years, feeling unheard.
Vindication came slowly. As molecular tools improved through the 1960s and 70s, transposable elements were found in bacteria, then in virtually every organism studied, including humans, where they make up a significant fraction of the genome. In 1983, McClintock became the first woman to win an unshared Nobel Prize in Physiology or Medicine, a belated recognition of a discovery that had quietly rewritten the rules of genetics.
Key people: Barbara McClintock