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Discovering the causes of cancer and the means of prevention

Thomas R. O'Brien, M.D., M.P.H.

Senior Investigator

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Phone: 240-760-6600

Thomas R. O'Brien, M.D., M.P.H.

Thomas R. O'Brien, M.D., M.P.H.

Organization:National Cancer Institute
Division of Cancer Epidemiology & Genetics, Infections and Immunoepidemiology Branch
Address:NCI Shady Grove
Room 6E108


Dr. O'Brien received undergraduate and medical degrees from the University of Michigan, and an M.P.H. from the Harvard School of Public Health. He was an Epidemic Intelligence Service Officer and Medical Epidemiologist with the Centers for Disease Control and Prevention before joining the NIH Intramural Research Program in 1992. His primary research interests have involved studies on the transmission and natural history of oncogenic viruses, including human immunodeficiency virus type 1, hepatitis B virus and hepatitis C virus (HCV).

Research Interests

Dr. O’Brien’s research program targets viruses that cause cancer, especially hepatitis C virus, through interdisciplinary studies that emphasize human genetics. He focuses on studies that may translate into clinical or public health benefits. Dr. O’Brien organized a trans-disciplinary group of investigators to refine understanding of the genetic basis for spontaneous HCV clearance and response to treatment for chronic hepatitis C. This collaboration led to the discovery of IFNL4, a novel gene that appears to underlie observed differences in HCV clearance (Prokunina-Olsson et al, Nature Genetics, 2013). His current work focuses on three areas: IFNL4 genotype-based clinical prediction models for response to treatment with direct-acting antiviral regimens for HCV infection; associations between IFNL4 genotype and other infections; and the role of other genetic variants in HCV clearance.