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Your Environment. Your Health.

Comparative & Molecular Pathogenesis Branch

The Comparative and Molecular Pathogenesis Branch (CMPB) provides toxicologic pathology leadership and laboratory animal medicine expertise to meet the goals of the NIEHS Division of the National Toxicology Program (DNTP) using new technologies in biomedical research. DNTP is a team-based scientific organization, and its mission is to improve public health through development of data and knowledge that are translatable, predictive, and timely.

A major function of the Branch is to provide a translational and mechanistic context to pathology outcomes with the integration of scientific data across all DNTP branches and offices. In addition, CMPB trains pathology and laboratory animal medicine fellows to be leaders in multidisciplinary research.

CMPB scientists and staff are responsible for the following general functions:

  • Developing new methods, approaches, and technologies in pathology and laboratory animal medicine.
  • Directing, managing, evaluating, and interpreting all pathology data generated during the conduct of DNTP toxicity and carcinogenicity studies.
  • Directing the DNTP laboratory animal medicine program.
  • Establishing standards, terminology, and diagnostic criteria for rodent pathology (NTP Nonneoplastic Lesion Atlas).
  • Investigating molecular mechanisms of spontaneous and chemically induced nonneoplastic and neoplastic lesions in DNTP studies.
  • Leading state-of the-science core pathology laboratories which include:
    • Clinical chemistry
    • Electron Microscopy
    • Hematology
    • Histology
    • Imaging Sciences/Artificial Intelligence
    • Immunohistochemistry
    • Laser Capture Microdissection
    • Mouse Embryo Phenotyping
    • Necropsies
  • Overseeing the scientific activities of the DNTP archives and frozen tissue bank.
  • Providing diagnostic pathology expertise and collaborations with NIEHS investigators and the NIEHS laboratory animal colony.

CMPB is organized into eight scientific groups that are led by board certified pathologists and laboratory animal medicine scientists, and fellows of the International Academy of Toxicologic Pathology.

Comparative and Molecular Pathogenesis Branch


Robert Sills, D.V.M., Ph.D.
Robert C. Sills, D.V.M., Ph.D.
Chief, Comparative and Molecular Pathogenesis Branch
Tel 984-287-3839
P.O. Box 12233
Mail Drop B3-06
Durham, N.C. 27709

Pathology Coordinator

Danica MK Andrews
Danica Andrews
Program Specialist

Tel 984-287-3882
Fax 919-541-0295

Support Staff

Portrait of Whitney Murphy
Whitney Murphy
Contractor — Operations Coordinator

Tel 984-287-4218
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