A genomic deletion marking an emerging subclone of Francisella tularensis subsp. holarctica in France and the Iberian Peninsula

Division of Microbiology, Armed Forces Institute of Pathology, Washington, DC, Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, Department of Food Science Technology, University of Nebraska at Lincoln, Lincoln, NE, Laboratoire de Bacteriologie, Centre Hospitalier et Universitaire, Nancy, France, Department of Animal Health Faculty of Veterinary Medicine, University of León, León, Spain, Modernization Directorate, Office of the Air Force Surgeon General, Falls Church, VA, Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ. Division of Infectious Diseases, Department of Clinical Microbiology, Umeå University, and Department of NBC-Analysis, Swedish Defence Research Agency, Umeå, Sweden

^* To whom correspondence should be addressed. Email: abenson1{at}unl.edu.

	Abstract

Francisella tularensis subsp. holarctica is widely disseminated in North America and the boreal and temperate regions of Eurasian continent. Comparative genomic analyses identified a 1.59 Kb genomic deletion specific to F. tularensis subsp. holarctica isolates from Spain and France. Phylogenetic analysis of strains carrying this deletion by multiple-locus variable-number tandem repeat analysis (MLVA) showed that the strains comprise a highly related set of genotypes, implying that these strains were recently introduced or recently emerged by clonal expansion in France and the Iberian Peninsula.