title: Divergence among an international population of Trichophyton tonsurans isolates.
abstract: Trichophyton tonsurans is a widely distributed pathogen that demonstrates a significant degree of genetic and phenetic heterogeneity. To date, the degree of genetic relatedness among geographically segregated isolates has not been explored. This investigation evaluates the extent of genetic variation among an international population of T. tonsurans isolates and examines the relatedness of isolates within and between countries. Molecular strain typing was performed on 198 isolates obtained from 14 countries. A mixed-marker strategy utilizing 27 sequence variations in 13 gene loci was applied to all isolates and cluster analysis was performed to examine the relationship between strains. Phylogenetic analysis was used to corroborate the findings of the cluster analysis with T. equinum strains serving as an out-group. In total, 47 distinct strain types were identified represented by seven clusters and one singleton. There appeared to be a moderate degree of clustering among isolates obtained from North America, Asia and Australia, although European isolates were uniformly distributed among the majority of clusters. The degree of genetic variation observed in this study coupled with the geographic localization would support the argument for allopatric divergence within this species.
authors.affiliation: Division of Clinical Pharmacology and Medical Toxicology, Children's Mercy Hospital, 2401 Gillham Road, Suite 0411, Kansas City, MO 64108, USA. srahman@cmh.edu
authors.forename: Susan M
authors.initials: SM
authors.lastname: Abdel-Rahman
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugita
authors.forename: Gloria M
authors.initials: GM
authors.lastname: González
authors.forename: David
authors.initials: D
authors.lastname: Ellis
authors.forename: Michalis
authors.initials: M
authors.lastname: Arabatzis
authors.forename: Loranne
authors.initials: L
authors.lastname: Vella-Zahra
authors.forename: Calude
authors.initials: C
authors.lastname: Viguié-Vallanet
authors.forename: Masataro
authors.initials: M
authors.lastname: Hiruma
authors.forename: J Steven
authors.initials: JS
authors.lastname: Leeder
authors.forename: Barry
authors.initials: B
authors.lastname: Preuett
mesh_terms: D001208:Asia; D001315:Australia; D004271:DNA, Fungal / Q000032:analysis / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000032:analysis / Q000235:genetics; D004641:Emigration and Immigration; D005060:Europe; D019143:Evolution, Molecular; D014644:Genetic Variation; D005843:Geography; D006801:Humans; D008969:Molecular Sequence Data; D009656:North America; D017422:Sequence Analysis, DNA; D014005:Tinea / Q000382:microbiology* / Q000635:transmission; D014249:Trichophyton / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D014774:Virulence / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer