Director: Robert Heflich, Ph.D.
Provide internationally recognized expertise in developing, validating, and interpreting genetic toxicology research for regulatory decisions that improve public health.
Division Research Themes
- Development, validation, and maintenance of regulatory genetic-toxicology assays
- Chemical-specific research
- Development of new paradigms for regulatory decision-making that Integrate measures of genetic risk with biomarkers of toxicity by conducting research Involving:
• Advanced more relevant biological models
• Comprehensive approaches to monitoring genetic variation using technologies such as Next Generation Sequencing (NGS)
• New approaches for evaluating data to determine human risk
The Division promotes public health by providing FDA with the expertise and tools necessary for comprehensive assessments of genetic risk and by strengthening approaches to integrate knowledge of genetic risk into regulatory decision-making. Division research is directed towards improving existing methods, and towards developing and validating new methods for evaluating high-priority issues related to the toxicity of food additives, human and animal drugs, biological therapies, nanomaterials, dietary supplements, tobacco products, botanicals, and medical devices. Division scientists actively participate in FDA committees and international working groups that form consensus on how to conduct regulatory genetic toxicology testing. These groups include the FDA GeneTox Network, FDA/CDER’s Genetic Toxicology Subcommittee, the International Workshop for Genotoxicity Testing (IWGT), the Organization for Economic Co-Operation and Development (OECD), and the International Life Sciences Institute/Health and Environmental Sciences Institute (ILSI/HESI).
2016 Major Research Accomplishments
- Completed a CTP-sponsored project measuring the toxicity and inflammation induced by whole smoke samples in an in vitro human air-liquid-interface airway culture.
- Started a project to explore the ability of using NGS for detecting somatic cell mutation induction by mutagenic carcinogens. This methodology has the potential to determine mutational load in the entire genome, regardless of the phenotype of the interrogated sequence or the tissue source of the DNA..
- Developed in vitro methods to assess global as well as gene-specific DNA methylation status using a single-cell gel electrophoresis assay.
- Conducted an OWH-funded project comparing the oncomutation profile of breast cancers in African American and Caucasian women.
- Started a new project to measure somatic oncomutations as biomarkers for translating preclinical safety data to human cancer risk.
- Developed a high fidelity NGS method called Mutational Analysis with Random DNA Identifiers (MARDI) to detect Pig-a gene mutations in heterogeneous CD48-deficient T-cell populations derived from carcinogen treated rats.
- In collaboration with CDER scientists, evaluated the hypothesis that rare oncogene mutations in human tumors are responsible for the failure of personalized medicine therapies by tracking mutation subpopulations in vitro in spheroid cultures generated from human-lung tumors.
- Investigated the use of NGS to measure low frequency cancer-relevant mutations in normal and tumor tissue, and started a new project to determine if NGS can be used to detect mutations from genotoxic carcinogens.
- Used dose-response modeling to evaluate the relative genotoxicity of a series of toxicants found in cigarette smoke as well as cigarette smoke samples prepared from different cigarettes.
- Published a manuscript on the utility of a transgenic hairless albino mouse mutational model for use in photogenotoxicity and photocarcinogenicity studies, and for assessing the safety of nanoparticles in cosmetics.
Research Plans for 2017
The following list is a sample of research projects being conducted at NCTR in the Division of Genetic and Molecular Toxicology.
- Conduct a new CTP-sponsored project utilizing the in vivo Comet assay to study inhalation exposure of a tobacco-specific toxicant in Sprague Dawley rats.
- Measure somatic oncomutations as biomarkers for translating preclinical safety data to human cancer risk.
- Set up a study to determine if NGS can be used to detect mutations from genotoxic carcinogens.
- Start a new project in collaboration with NIEHS and NTP using the newly developed epicomet assay to test the genotoxicity and epigenetic modifications of black cohosh extract in human cells.
- Start a new study in collaboration with CBER testing the off-target mutagenicity of CRISPR mediated genome editing in mammalian cells.
- Start a project involving an immunotoxicity assessment of nanomaterials using human immune cell-based biomarkers of innate immunity.
- Develop methods for evaluating Pig-a mutations in rat granulocytes and erythroid precursor cells.
NCTR's Annual Report contains information on the latest accomplishments and plans for the Division of Genetic and Molecular Toxicology as well as project and publication listings.