Our Science – Johnson Website

Warren E Johnson, Ph.D.

Laboratory of Genomic Diversity Genetics Section Staff Scientist LGD NCI-Frederick Frederick, MD 21702-1201 Phone:   301-696-7483 Fax:   301-696-6327 E-Mail:   JOHNSONW@NCIFCRF.GOV

Biography

Warren Johnson earned his Ph.D. in Animal Ecology from Iowa State University in 1992 after receiving an M.S. in Wildlife Ecology from Utah State University in 1984 and a B.A. in Biology from Oberlin College in 1983. He has been with the Laboratory of Genomic Diversity since 1992, first as a visiting scientist from the National Zoological Park, Smithsonian Institution. Warren has traveled extensively around the world studying wildlife species and collecting samples for studies on infectious disease, mammalian evolution, comparative genomics, and genetic mapping in model organisms.

Research

Comparative Genomics

The primary objective of our research is to develop and utilize comparative genomics and phylogenetic tools to study free-ranging populations for taxonomic, adaptive, and hereditary disease inference. This includes the development of animal models for the study of viral diseases and gene discovery in free-ranging mammalian species.

Exotic species have demonstrated their utility as models for the study of a wide range of hereditary and infectious diseases and physical traits. However, to fully interpret the results of these studies, it is necessary to understand their evolutionary history. This involves not only a more precise description of the phylogenetic relationships among species, but also an assessment of the uniqueness among wild populations and knowledge of historic patterns of gene flow. Our primary animal model has been the domestic cat and their exotic relatives and wild populations. As crucial step in this process, we have developed the foremost collection of biological samples from captive and wild populations of cats, which has provided the theoretical and conceptual framework for our research. The soon-to-be-released whole genome sequence of the domestic cat will provide another important tool for our research and will greatly accelerate the pace of gene discovery and comparative genomic inference.

Among the cat species, we have recently focused efforts on Asian species, including the tiger, leopard, clouded leopard, leopard cat, and fishing cat, as well as Canada lynx, bobcat, and puma. Many of these studies integrate and focus on host/virus interactions, such as with FeLV and FIV in Florida Panthers and FIV and CDV in African lions.

Our comparative genomic studies have expanded to include the alpaca and the pangolin. We will complete development of a radiation hybrid (RH) map of the alpaca in 2006 which will facilitate the study of candidate genes for inherited diseases in camelids and related ungulate species, including several related to human disorders. Study of the pangolin, a group of species distributed in Africa and Asia and the closest relatives to carnivores, will provide good models for comparative genomic studies among these increasingly well-studied groups. Our research on camelids and pangolins will be increasingly important given the inclusion of both the alpaca and the pangolin on the short list of species for low-coverage, whole-genome-sequencing.

Collaborators on these research projects include Dr. Christine Breitenmoser-Wursten, IUCN/SSC Cat Specialist Group; Dr. Bill Clark, Iowa State University; Dr. Melanie Culver, Arizona Cooperative Fish & Wildlife Research Unit; Dr. Eduardo Eizirik, PUCRS, Brazil; Dr. Todd Fuller, University of Massachusetts; Dr. Philip Gaubert, Institut de Recherche pour le Dveloppement; Dr. Agustin Iriarte, Universidad Mayor, Chile; Darrell Land, Florida Fish and Wildlife Conservation Commission; Dr. David Macdonald, University of Oxford; Dr. Juan Carlos Marín, Universidad Catolica, Chile; Dr. Bill Murphy, Texas A&M University; Mike O'Brien, Nova Scotia Dept. Natural Resources; Dr. Linda Penfold, White Oak Conservation Center; Dr. Emma Teeling, University College of Dublin; Dr. David Wildt, Smithsonian Institution.

This page was last updated on 7/15/2008.