Roy J. Britten discovered repeated DNA sequences in higher organisms' genomes. Britten conducted research on repetitive DNA and its origins which provided a foundation for advanced genetic investigations regarding human evolution. Britten's molecular evolution research benefited from the work of cytogeneticist Barbara McClintock (1902-1992). She hypothesized in the 1940s that DNA sequences were not always static because some genetic elements moved on or between chromosomes resulting in physical variations in organisms, due to the presence or absence of genes. Although McClintock's jumping gene theory was not immediately understood, molecular biologists gradually identified these mobile elements as transposons and began to study their role in evolution. Britten was one of the first researchers to detect transposons in mammal genomes.

Born in Washington, D.C., Britten became enthusiastic about science as a child. His physics studies at the University of Virginia were interrupted when he was invited to work on...