Dr. Guo-Min Li is a professor of Radiation Oncology and Director of the Reece A. Overcash Jr. Center for Research on Colon Cancer, in Honor of Dr. Eugene Frenkel, at UT Southwestern. He received his BS and MS degrees in biology from Wuhan University in China and his Ph.D. degree in chemistry from Wayne State University. He performed his postdoctoral training with Nobel laureate Dr. Paul Modrich (Chemistry, 2015) at Duke University. Before joining UT Southwestern, Dr. Li held professorship at the University of Kentucky and the University of Southern California.

Dr. Li studies DNA mismatch repair (MMR), an important cellular mechanism that ensures replication fidelity. His work has contributed to the understanding of MMR and its role in cancer susceptibility and therapy. He discovered MMR defects as the genetic basis of hereditary non-polyposis colorectal cancer and sporadic colorectal cancers displaying microsatellite instability. He identified and characterized the majority of components required for human MMR, and reconstituted the human MMR reaction in vitro. Recently, his laboratory has discovered epigenetic factors as important MMR components/regulators, including histone modifications and non-coding RNAs. He is also responsible for discovering the apoptotic function of MMR, in which MMR proteins recognize chemically and physically adducted DNA and trigger a futile repair cycle to induce cell death, implicating MMR in cancer therapy. In addition, his lab has also elucidated the mechanism by which the mismatch repair system promotes (CAG)•(CTG) trinucleotide repeat expansion that causes many neurodegenerative disorders.


Wuhan University (1982), Botany
Graduate School
Wuhan University (1985), Genetics
Graduate School
Wayne State University (1991), Chemistry

Research Interest

  • DNA mismatch repair in neurodegenerative diseases
  • Mechanistic studies of DNA mismatch repair
  • Targeting DNA mismatch repair factors in cancer therapy


Featured Publications LegendFeatured Publications

DNA mismatch repair preferentially safeguards actively transcribed genes.
Huang Y, Li GM DNA Repair (Amst.) 2018 Aug
A human MUTYH variant linking colonic polyposis to redox degradation of the [4Fe4S]2+ cluster.
McDonnell KJ, Chemler JA, Bartels PL, O'Brien E, Marvin ML, Ortega J, Stern RH, Raskin L, Li GM, Sherman DH, Barton JK, Gruber SB. Nature Chem 2018 10 8 873-880

Professional Associations/Affiliations

  • Professor, UT Southwestern (2017)
  • Professor, University of Southern California (2015-2017)
  • Professor, University of Kentucky (1995-2015)
  • Postdoctoral fellow, Duke University (1991-1995)