Simpson Memorial Lecture on 5 March 2007

26 February 2007—Randy L. Jirtle, professor of radiation oncology and associate professor of pathology at Duke University, will present the Robert T. Simpson Memorial Lecture in Molecular Medicine at 4:00 p.m. on Monday, 5 March 2007, in 102 Thomas Building on the Penn State University Park campus. This free public lecture, titled "Environmental Epigenomics and Disease Susceptibility," is sponsored by the Department of Biochemistry and Molecular Biology.

Jirtle's research focuses on the fields of epigenetics, genomic imprinting, and cancer. Genomic imprinting occurs when the expression of a gene varies depending on whether it is inherited from the mother or the father. Jirtle identified the imprinted IGF2R GENE as a tumor-suppressor gene whose inactivation increases the tumor's resistance to radiation therapy. He holds two U.S. patents based on this finding. Jirtle also was the first to discover a novel imprinted-chromosome region that contains the imprinted genes DLK1 and GTL2. He subsequently identified another mutation located in the same imprinted-chromosome region, whose presence in sheep results in the enlargement of fast-twitch muscle tissue.

Jirtle recently demonstrated that, in a certain strain of laboratory mice, feeding the mother a compound that can donate methyl groups to the pups' DNA during gestation caused changes in the baby mice that became evident when they became adults. His research also revealed that this effect occurred by the alteration of the promoter of the Agouti gene, rather than by direct mutation of that gene. To identify additional genes that are easily modified by environmental influences, Jirtle has used machine-learning algorithms for the genome-wide prediction of imprinted genes.

Jirtle received a bachelor's degree in nuclear engineering and a doctoral degree in radiation biology from the University of Wisconsin at Madison in 1970 and 1976, respectively.  He has published over 150 research articles, authored several invited book chapters, and edited the book Liver Regeneration and Carcinogenesis: Molecular and Cellular Mechanisms. In 1995, he established the genomic-imprinting website geneimprint.com, to further research in this rapidly growing scientific field. He has been invited to present a number of named lectureships, and was invited to speak at the 2004 Nobel Symposium on epigenetics.

The Simpson Memorial Lectureship honors Robert T. Simpson, formerly the Verne M. Willaman Professor of Molecular Biology, and is made possible through donations from his family, friends, and colleagues. For more than 35 years, Simpson was an international leader in research on chromatin--a fundamental component of chromosomes--and its role in gene regulation. He was at the National Institutes of Health from 1970 until 1995, when he came to Penn State. His addition to the faculty of the Department of Biochemistry and Molecular Biology is considered to have contributed substantially to placing Penn State, and the department, at the forefront of chromatin research, and to have greatly enhanced Penn State's research and educational missions.

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