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

• Autor(a) principal: Fontes, Amanda Nogueira Brum
• Data de Publicação: 2012
• Outros Autores: Gomes, Harrison Magdinier, Araujo, Marcelo Ivens de, Albuquerque, Edson Cláudio Araripe de, Baptista, Ida Maria Foschiani Dias, Moura, Maria Manuela da Fonseca, Rezende, Denise Silva, Pessolani, Maria Cristina Vidal, Lara, Flavio Alves, Pontes, Maria Araci de Andrade, Gonçalves, Heitor de Sá, Silva, Norma Lucena, Sarno, Euzenir Nunes, Vissa, Varalakshmi D., Brennan, Patrick J., Suffys, Philip Noel
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da FIOCRUZ (ARCA)
• Texto Completo: https://www.arca.fiocruz.br/handle/icict/16183
• topic: Mycobacterium leprae; Epidemiologia molecular; Genótipos; Polimorfismos de nucleotídeo único; Biópsia da pele; Hanseníase; Brasil; Mycobacterium leprae; Ziehl-Neelsen-stained microscope slides; molecular epidemiology; variable number tandem repeats; single-nucleotide polymorphisms; skin biopsy; Leprosy; Brazil

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.