| Área: Micobacteriologa ( Divisão C ) GENOTYPING OF MYCOBACTERIUM LEPRAE FROM BRAZILIAN LEPROSY PATIENTS
Amanda Nogueira Brum Fontes (FIOCRUZ); Rama Murthy Sakamuri Sakamuri (CSU); Ida Maria F. Dias Baptista Baptista (ILSL); Somei Ura Ura (ILSL); Harrison Magdinier Gomes Gomes (FIOCRUZ); Edson Cláudio A. de Albuquerque Albuquerque (FIOCRUZ); Milton Ozório Moraes Moraes (FIOCRUZ); Alejandra Nóbrega Martinez Martinez (FIOCRUZ); Euzenir Nunes Sarno Sarno (FIOCRUZ); Philip Noel Suffys Suffys (FIOCRUZ); Varalakshmi D. Vissa Vissa (CSU); Patrick J. Brennan Brennan (CSU); Denise Silva Rezende Rezende (UNIR); Maria Manuela da F. Moura Moura (UNIR)
ResumoIntroduction. Leprosy is caused by infection with Mycobacterium leprae, an obligate intracellular parasite and it remains a major health problem in several developing countries. Since 2000, variable number of tandem repeats (VNTR) have been exploited in the M. leprae genome and in 2005, three single nucleotide polymorphism (SNP) were also discovered to be useful for analysis of the global spread of leprosy. Nowadays the detection of strain variation in areas with high prevalence of leprosy is possible, thus allowing more profound transmission and phylogeny studies.
Methods. In this study, we present data obtained based on examination of the allelic diversity of 16 select VNTR and three SNP loci in M. leprae genome. Clinical isolates obtained from skin biopsies samples and Ziehl-Neelsen stained microscopic slides from Rio de Janeiro, São Paulo and Rondônia were analyzed (n=133).
Results and conclusions. Using a PCR-RFLP-based procedure, the characterization of the main M. leprae genotypes was found to be more straightforward and we observed that the SNP type 3 was most frequent, followed by SNP type 4. The allelic patterns of two minisatellite loci 27-5 and 12-5 were highly correlated with SNP type 3. Our results, besides providing additional data showing the relation between different genetic markers, suggest that VNTR analysis in M. leprae is not very different from that observed in other Mycobacterium species. The allelic index for each locus ranged between zero to 0.92. Epidemiological association between genotypes and disease form, origin or other patient characteristics was not evident in this study population and requires further investigation. Our preliminary data obtained with material extracted from Ziehl-Neelsen stained slides also suggested that this material could serve as an alternative or additional source for M. leprae genotyping.
Palavras-chave: Genotyping, Mycobacterium leprae, VNTR, SNP |