Lorraine Symington is a geneticist recognized for her work on mechanisms of homologous recombination. She is known particularly for her work using the budding yeast model system to decipher how DNA double-strand breaks are repaired. Symington was born on Foulness Island, Essex, UK. She graduated from the University of Sussex with a degree in Biology in 1979, and from the University of Glasgow in 1982 with a Ph.D. in Genetics. She moved to the US for post-doctoral studies at the Dana Farber Cancer Institute (affiliated with Harvard Medical School) and at the University of Chicago. Symington joined the faculty in the Department of Microbiology, College of Physicians and Surgeons at Columbia University Medical Center in 1988. She is currently the Harold S. Ginsberg Professor of Microbiology and Immunology and Professor of Genetics and Development at Columbia University Irving Medical Center. She is a fellow of the American Academy of Microbiology and the American Association for the Advancement of Science, and a member of the American Academy of Arts and Sciences and the National Academy of Sciences.

Research Interests

Lorraine Symington's research is focused on understanding the mechanism of homologous recombination, which is critical for error-free repair of DNA double-strand breaks (DSBs) and tolerance of replication stress. Her laboratory has developed innovative genetic assays to identify the genes controlling recombination in budding yeast, and employed physical monitoring methods coupled with genetic analysis to define the steps catalyzed by each corresponding protein. Symington is particularly well known for her work elucidating how the ends of DSBs are processed, a critical step to initiate homology-directed repair. Her work led to the commonly accepted model that end processing occurs by a two-step mechanism, the first catalyzed by the evolutionarily conserved Mre11 complex, and the second involving two functionally redundant nucleases, Exo1 and Sgs1-Dna2. She is also known for her studies demonstrating that homologous recombination proceeds via a metastable strand invasion intermediate involving cycles of strand invasion and dissociation. In addition, her research has yielded novel insights into the mechanism of break-induced replication, the role of the single-stranded DNA binding protein RPA in preventing genome rearrangements, and the identification of nucleases involved in resolution of recombination intermediates.

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Primary Section

Section 26: Genetics

Secondary Section

Section 21: Biochemistry