Rutgers-The State University of New Jersey, New Brunswick, NJ; B.A. in Biology, 1968; M.S. in Bacteriology, 1970; Ph.D. in Microbiology, 1976.

Experience:

• 1968-1970, Research Assistant, Rutgers University.
• 1970-1972, Biological Research Assistant, Maxillofacial Research Division, Letterman Army Institute of Research, San Francisco, CA.
• 1972-1975, Teaching Assistant, Busch Pre-doctoral Fellow, Rutgers University.
• 1975-1976, Research Associate, Michigan Cancer Foundation, Detroit, MI.
• 1976-1979, Research Associate, Michigan State University, E. Lansing, MI.
• 1979-1983, Microbiologist, V.A. Medical Center, Little Rock, AR.
• 1983-present, Microbiologist, Food and Drug Administration, National Center for Toxicological Research, Division of Genetic and Reproductive Toxicology, Jefferson, AR.
• 1997-present, Adjunct Professor, Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences.

Current Primary Research Interests: Genetic Toxicology

• Development of approaches to measure and analyze mutations in laboratory animals:
• Transgenic shuttle vector systems employing the lacI and FX174 am3 reporter genes
• Mouse and rat systems employing the endogenous X-linked Hprt gene as a reporter of mutation and a mouse model that measures mutation in the endogenous autosomal Tk gene
• Using the mismatch binding protein MutS in a scheme that detects mutations solely on alterations in DNA sequence (genotypic selection)
• Application of sensitive and predictive in vivo mutation assays for carcinogen risk assessments.

Selected Recent Publications (from a total of over 150):

• Chen, T., A. Aidoo, M.G. Manjanatha, R.A. Mittelstaedt, S.D. Shelton, L.E. Lyn-Cook, D.A. Casciano and R.H. Heflich (1998) Comparison of mutant frequencies and types of mutations induced by thiotepa in the endogenous Hprt gene and transgenic lacI gene of Big Blue rats, Mutation Res., 403, 199-214.

• Parsons, B.L., and R.H. Heflich (1998) Detection of basepair substitution mutation at a frequency of 1 x 10^-7 by combining two genotypic selection methods, MutEx enrichment and allele-specific competitive blocker PCR, Environ. Mol. Mutagenesis, 32, 200-211.

• Chen, J.B., S.B. Dass, J.G. Burkhart and R.H. Heflich (1998) Sensitivity of the FX174 am3 allele in relation to the endogenous Hprt gene for detecting mutation in transgenic mice, Environ. Mol. Mutagenesis, 32, 229-235.

• Chen, T., A. Aidoo, R.A. Mittelstaedt, D.A. Casciano and R.H. Heflich (1999) Hprt mutant frequency and molecular analysis of Hprt mutations in Fischer 344 rats treated with thiotepa, Carcinogenesis, 20, 269-277.

• Dobrovolsky, V.N., D.A. Casciano and R.H. Heflich (1999) Tk^+/- mouse model for detecting in vivo mutation in an endogenous, autosomal gene, Mutation Res., 423, 125-136.

• Dass, S.B., T.J. Bucci, R.H. Heflich and D.A. Casciano (1999) Evaluation of the transgenic p53^+/- mouse for detecting genotoxic liver carcinogens in a short-term bioassay, Cancer Lett., 143, 81-85.

• Dobrovolsky, V.N., T. Chen and R.H. Heflich (1999) Molecular analysis of in vivo mutations induced by N-ethyl-N-nitrosourea in the autosomal Tk and the X-linked Hprt genes of mouse lymphocytes, Environ. Mol. Mutagenesis, 34, 30-38.

• Mittelstaedt, R.A., B.A. Smith, T. Chen, F.A. Beland and R.H. Heflich (1999) Sequence specificity of Hprt lymphocyte mutation in rats fed the hepatocarcinogen 2-acetylaminofluorene, Mutation Res., 431, 167-173.

• Heflich, R.H, and D.A. Casciano (2000) In vivo gene mutation assays and their application in cancer risk assessment, Mutation Res. Forum, in press.

• Dobrovolsky, V.N., J.G. Shaddock and R.H. Heflich (2000) 7,12-Dimethylbena[a]anthracene-induced mutation in the Tk gene of Tk^+/- mice; Automated scoring of lymphocyte clones using a fluorescent viability indicator, Environ. Mol. Mutagenesis, in press.