John Rapp, Ph.D., D.V.M.
Professor Emeritus
Dr. John Paul Rapp, who is a pioneer in the field of quantitative genetics, established the foundation for the study of blood pressure using segregating rodent populations while he was a distinguished faculty member of our Institution since 1976. He was also the recipient of the Helen and Harold McMaster Endowed Chair in Biochemistry and Molecular Biology.
Together with Dr. Lewis K. Dahl, he published the first study of an intermediate phenotype of blood pressure as a quantitative trait. This seminal work constituted the first rational approach for the identification of a quantitative trait locus (QTL) for blood pressure and was accomplished more than a decade before modern molecular markers became available. Dr. Rapp’s research accomplishments in Toledo include the development of inbred strains of the Dahl salt sensitive (SS/Jr) and Dahl salt resistant (SR/Jr) rats, where Jr stands for John Rapp. These strains are widely used models for the physiology and genetics of blood pressure control. The Rapp paradigm for identifying the primary genetic causes of hypertension in animal models serves as a roadmap for the identification of blood pressure QTLs and the underlying causative genes. His laboratory was the first to use an animal model of hypertension along with molecular markers to identify: 1) Sixteen chromosomal regions within the rat genome that are linked to the trait of blood pressure, 2) Mutations in a gene (11ß-hydroxylase) linked to altered enzyme activity explaining the differences in blood pressure between rat strains, 3) Epistatically interacting blood pressure QTLs in segregating rat populations and 4) Confirmation of epistatic interaction using congenic and double congenic strains.
Dr. Rapp is a recipient of numerous national and international awards including the CIBA Award for Hypertension Research, MERIT award from the NIH, Career Achievement Award from the Medical College of Ohio, Humboldt Research Award for Senior Scientists from the Alexander von Humboldt Foundation in Germany. Since his retirement in 2004 as Professor and Chairman of the Department of Physiology and Cardiovascular Genomics, Dr. Rapp has sustained his primary research interest in the Genetics of Hypertension through interactions with the laboratories of his successors within the Department, Drs. Bina Joe and George T. Cicila.