title: Frequency and genetic diversity of the MAT1 locus of Histoplasma capsulatum isolates in Mexico and Brazil.
abstract: The MAT1-1 and MAT1-2 idiomorphs associated with the MAT1 locus of Histoplasma capsulatum were identified by PCR. A total of 28 fungal isolates, 6 isolates from human clinical samples and 22 isolates from environmental (infected bat and contaminated soil) samples, were studied. Among the 14 isolates from Mexico, 71.4% (95% confidence interval [95% CI], 48.3% to 94.5%) were of the MAT1-2 genotype, whereas 100% of the isolates from Brazil were of the MAT1-1 genotype. Each MAT1 idiomorphic region was sequenced and aligned, using the sequences of the G-217B (+ mating type) and G-186AR (- mating type) strains as references. BLASTn analyses of the MAT1-1 and MAT1-2 sequences studied correlated with their respective + and - mating type genotypes. Trees were generated by the maximum likelihood (ML) method to search for similarity among isolates of each MAT1 idiomorph. All MAT1-1 isolates originated from Brazilian bats formed a well-defined group; three isolates from Mexico, the G-217B strain, and a subgroup encompassing all soil-derived isolates and two clinical isolates from Brazil formed a second group; last, one isolate (EH-696P) from a migratory bat captured in Mexico formed a third group of the MAT1-1 genotype. The MAT1-2 idiomorph formed two groups, one of which included two H. capsulatum isolates from infected bats that were closely related to the G-186AR strain. The other group was formed by two human isolates and six isolates from infected bats. Concatenated ML trees, with internal transcribed spacer 1 (ITS1) -5.8S-ITS2 and MAT1-1 or MAT1-2 sequences, support the relatedness of MAT1-1 or MAT1-2 isolates. H. capsulatum mating types were associated with the geographical origin of the isolates, and all isolates from Brazil correlated with their environmental sources.
authors.affiliation: Departamento de Microbiología-Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México DF, Mexico.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Rodríguez-Arellanes
authors.forename: Carolina
authors.initials: C
authors.lastname: Nascimento de Sousa
authors.forename: Mauro
authors.initials: M
authors.lastname: de Medeiros-Muniz
authors.forename: José A
authors.initials: JA
authors.lastname: Ramírez
authors.forename: Cláudia V
authors.initials: CV
authors.lastname: Pizzini
authors.forename: Marcos
authors.initials: M
authors.lastname: de Abreu-Almeida
authors.forename: Manoel M
authors.initials: MM
authors.lastname: Evangelista de Oliveira
authors.forename: Ana-Marisa
authors.initials: AM
authors.lastname: Fusco-Almeida
authors.forename: Tania
authors.initials: T
authors.lastname: Vite-Garín
authors.forename: Nayla S
authors.initials: NS
authors.lastname: Pitangui
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Estrada-Bárcenas
authors.forename: Antonio E
authors.initials: AE
authors.lastname: González-González
authors.forename: María José Soares
authors.initials: MJ
authors.lastname: Mendes-Giannini
authors.forename: Rosely M
authors.initials: RM
authors.lastname: Zancopé-Oliveira
authors.forename: Maria-Lucia
authors.initials: ML
authors.lastname: Taylor
mesh_terms: D001483:Base Sequence; D001938:Brazil; D021901:DNA, Intergenic / Q000235:genetics; D049770:Genes, Mating Type, Fungal / Q000235:genetics*; D056426:Genetic Loci / Q000235:genetics*; D014644:Genetic Variation; D006658:Histoplasma / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D016013:Likelihood Functions; D008800:Mexico; D008969:Molecular Sequence Data
chemical_list: D021901:DNA, Intergenic