Biography:

Dr. Johnson earned his PhD in Animal Ecology from Iowa State University in 1992 after receiving an MS in Wildlife Ecology from Utah State University in 1984 and a BA in Biology from Oberlin College in 1983. He has been with the Laboratory of Genomic Diversity since 1992. Dr. Johnson specializes in comparative genomics, molecular ecology, population genetics, conservation genetics, and evolutionary biology. Dr. Johnson currently serves as the Scientific Advisor for the Student Intern Program (SIP) for High School students and as co-secretary of the CCR-Staff Scientist / Staff Clinician Organization.

Research:

The primary objective of our collaborative research projects is to develop and utilize comparative genomics and phylogenetic tools 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.

1. Comparative Genomics of Mammals
   Comparative genomic studies allow for annotation of the human genome sequence by studying the landscape of genome organization in other mammal species. The LGD is the leader in comparative genome inference, diseases and model development using the domestic cat and its relatives in the cat family Felidae. The goal of this project is to continue the development of the cat model for human gene annotation and for human disease etiology. More recently this expertise and methodology is being applied to other species, including the development of a radiation hybrid map and whole genome amplification for the alpaca and pangolin, each of which offer important opportunities for interpreting gene evolution and disease gene discovery in models of human hereditary diseases and phenotypes.
2. Comparative Virology and Emerging Infectious Agents.
   Many pathogens in animal reservoirs erupt in human populations. The goals of this research is to cooperate with veterinarians, wildlife biologists, and government and non-government organizations to assemble an unrivalled collection of animal biomedical specimen tissue, blood, serum, sperm, skin fibroblasts for study, discovery, and surveillance of pathogens. Further these studies provide important animal model for study of genetic and immune adaptation to defend against pathogenesis. The principle aims of this research are to characterize the genomic patterns of infectious agents (FIV, FeLV,FeCV) in free ranging species as a means to retrace the natural history of deadly pathogens in model species, to assess the interaction of confounding viral infections in natural settings to understand co-infection influences on pathogenesis, to investigate the intersection of host versus viral genomes in viral genetic divergence during the progression of outbreaks, and to develop novel approaches for pathogen detection and also for understanding viral disease pathogenesis.
3. Natural History Studies
   A comparative genomic approach to cancer, infectious disease and biological processes requires an understanding of the evolutionary history of the species and populations being compared. The natural history of mammal species is a fascinating biological narrative that forms the framework for species divergence adaptation, survival and resilience to daily challenges, particularly deadly disease. Our goals are to assemble a biological tissue specimen collection with which to identify species, populations, and individuals, and to resolve historical, evolutionary, and pathogen relationships, and to employ the evolutionary comparative perspective to investigate mechanism for natural defense against infection disease and cancer. Recently these studies have included species of pangolins, carnivores, felids, canids, and camelids.

Publications:

Buckley-Beason, V.A., W.E. Johnson, W. Nash, R. Stanyon, J. Menninger, C.A. Driscoll, J. G. Howard, M. Bush, J.E. Page, M.E. Roelke, G. Stone, P. Martelli, C. Wen, L. Ling, R.K. Duraisingam, P.V. Lam, and S.J. O'Brien. 2006. Molecular evidence for species-level distinction in modern clouded leopards (Neofelis nebulosa). Current Biology.

Jae-Heup Kim, A. Antunes, S. Luo, J. Menninger, W.G. Nash, S.J. O'Brien, W.E. Johnson. 2006. Evolutionary analysis of a large mtDNA translocation (numt) into the nuclear genome of the Panthera genus species. Gene. 366:292-302.

Troyer JL, Pecon-Slattery J, Roelke ME, Johnson W, VandeWoude S, Vazquez-Salat N, Brown M, Frank L, Woodroffe R, Winterbach C, Winterbach H, Hemson G, Bush M, Alexander KA, Revilla E, O'Brien SJ . Seroprevalence and genomic divergence of circulating strains of feline immunodeficiency virus among Felidae and Hyaenidae species. J Virol . 79: 8282-94, 2005. [Journal]

O'Brien SJ, Johnson WE . Big cat genomics. Annu Rev Genomics Hum Genet . 6: 407-29, 2005. [Journal]

Luo SJ, Kim JH, Johnson WE, van der Walt J, Martenson J, Yuhki N, Miquelle DG, Uphyrkina O, Goodrich JM, Quigley HB, Tilson R, Brady G, Martelli P, Subramaniam V, McDougal C, Hean S, Huang SQ, Pan W, Karanth UK, Sunquist M, Smith JL, O'Brien SJ . Phylogeography and genetic ancestry of tigers (Panthera tigris). PLoS Biol . 2: e442, 2004. [Journal]

Johnson WE, Godoy JA, Palomares F, Delibes M, Fernandes M, Revilla E, O'Brien SJ . Phylogenetic and phylogeographic analysis of Iberian lynx populations. J Hered . 95: 19-28, 2004. [Journal]

Eizirik E, Yuhki N, Johnson WE, Menotti-Raymond M, Hannah SS, O'Brien SJ . Molecular genetics and evolution of melanism in the cat family. Curr Biol . 13: 448-53, 2003. [Journal]

Palomares F, Godoy JA, Piriz A, O'Brien SJ . Faecal genetic analysis to determine the presence and distribution of elusive carnivores: design and feasibility for the Iberian lynx. Mol Ecol . 11: 2171-82, 2002. [Journal]

Murphy, W. J., E. Eizirik, W. E. Johnson, Y. P. Zhang, O. A. Ryder, and S. J. O'Brien. 2001. Molecular phylogenetics and the origins of placental mammals. Nature. 409:614-618.