title: Genotyping of Mycobacterium leprae present on Ziehl-Neelsen-stained microscopic slides and in skin biopsy samples from leprosy patients in different geographic regions of Brazil.
abstract: We analysed 16 variable number tandem repeats (VNTR) and three single-nucleotide polymorphisms (SNP) in Mycobacterium leprae present on 115 Ziehl-Neelsen (Z-N)-stained slides and in 51 skin biopsy samples derived from leprosy patients from Ceará (n = 23), Pernambuco (n = 41), Rio de Janeiro (n = 22) and Rondônia (RO) (n = 78). All skin biopsies yielded SNP-based genotypes, while 48 of the samples (94.1%) yielded complete VNTR genotypes. We evaluated two procedures for extracting M. leprae DNA from Z-N-stained slides: the first including Chelex and the other combining proteinase and sodium dodecyl sulfate. Of the 76 samples processed using the first procedure, 30.2% were positive for 16 or 15 VNTRs, whereas of the 39 samples processed using the second procedure, 28.2% yielded genotypes defined by at least 10 VNTRs. Combined VNTR and SNP analysis revealed large variability in genotypes, but a high prevalence of SNP genotype 4 in the Northeast Region of Brazil. Our observation of two samples from RO with an identical genotype and seven groups with similar genotypes, including four derived from residents of the same state or region, suggest a tendency to form groups according to the origin of the isolates. This study demonstrates the existence of geographically related M. leprae genotypes and that Z-N-stained slides are an alternative source for M. leprae genotyping.
authors.affiliation: Laboratório de Biologia Molecular Aplicada a Micobactérias, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brasil. amandabrum@gmail.com
authors.forename: Amanda Nogueira Brum
authors.initials: AN
authors.lastname: Fontes
authors.forename: Harrison Magdinier
authors.initials: HM
authors.lastname: Gomes
authors.forename: Marcelo Ivens de
authors.initials: MI
authors.lastname: Araujo
authors.forename: Edson Cláudio Araripe de
authors.initials: EC
authors.lastname: Albuquerque
authors.forename: Ida Maria Foschiani Dias
authors.initials: IM
authors.lastname: Baptista
authors.forename: Maria Manuela da Fonseca
authors.initials: MM
authors.lastname: Moura
authors.forename: Denise Silva
authors.initials: DS
authors.lastname: Rezende
authors.forename: Maria Cristina Vidal
authors.initials: MC
authors.lastname: Pessolani
authors.forename: Flávio Alves
authors.initials: FA
authors.lastname: Lara
authors.forename: Maria Araci de Andrade
authors.initials: MA
authors.lastname: Pontes
authors.forename: Heitor de Sá
authors.initials: Hde S
authors.lastname: Gonçalves
authors.forename: Norma
authors.initials: N
authors.lastname: Lucena-Silva
authors.forename: Euzenir Nunes
authors.initials: EN
authors.lastname: Sarno
authors.forename: Varalakshmi D
authors.initials: VD
authors.lastname: Vissa
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Brennan
authors.forename: Philip Noel
authors.initials: PN
authors.lastname: Suffys
mesh_terms: D015373:Bacterial Typing Techniques; D001706:Biopsy; D001938:Brazil; D004269:DNA, Bacterial / Q000032:analysis*; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007918:Leprosy / Q000382:microbiology*; D009166:Mycobacterium leprae / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D013194:Staining and Labeling
chemical_list: D004269:DNA, Bacterial