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Pena S.D.J.,GENE Nucleo de Genetica Medica | Pena S.D.J.,Federal University of Minas Gerais | Coimbra R.L.M.,State University Londrina
Clinical Genetics | Year: 2015

We have recently performed exome analysis in a 7year boy who presented in infancy with an encephalopathy characterized by ataxia and myoclonic epilepsy. Parents were not consanguineous and there was no family history of the disease. Exome analysis did not show any pathogenic variants in genes known to be associated with seizures and/or ataxia in children, including all known human channelopathies. However, we have identified a mutation in KCNA2 that we believe to be responsible for the disease in our patient. This gene, which encodes a member of the potassium channel, voltage-gated, shaker-related subfamily, has not been previously described as a cause of disease in humans, but mutations of the orthologous gene in mice (Kcna2) are known to cause both ataxia and convulsions. The mutation is c.890C>A, leading to the amino acid substitution p.Arg297Gln, which involves the second of the critical arginines in the S4 voltage sensor. This mutation is characterized as pathogenic by five different prediction programs. RFLP analysis and Sanger sequencing confirmed the presence of the mutation in the patient, but not in his parents, characterizing it as de novo. We believe that this discovery characterizes a new channelopathy. © 2015 John Wiley & Sons A/S.

Alvim L.B.,Federal University of Minas Gerais | Sandes S.H.C.,Federal University of Minas Gerais | Silva B.C.,Federal University of Minas Gerais | Steinberg R.S.,Federal University of Minas Gerais | And 6 more authors.
Beneficial Microbes | Year: 2016

Diarrhoea in piglets by Salmonella and other pathogens can be a serious health problem. Non-drug treatments such as probiotic microorganisms have various effects on the gastrointestinal microbiota dysbiosis and host immune system modulation. The aim of this study was to demonstrate the suitable use of Weissella paramesenteroides WpK4 strain isolated from healthy piglets as an alternative prophylactic or therapeutic treatment against Salmonella Typhimurium. Out of 37 lactic acid bacteria isolates, 24 strains belonging to the Weissella and Lactobacillus genera were analysed in vitro for desirable probiotic characteristics. The W. paramesenteroides WpK4 strain fulfilled all in vitro tests: resistance to acidic pH and bile salts, hydrophobic cell surface, antagonism against bacterial pathogens, H2O2 production and exopolysaccharide secretion, and non-transferable resistance to antibiotics. Mice fed with WpK4 showed no signs of bacterial translocation to the liver or spleen and decreased Salmonella translocation to these organs. Significantly, WpK4 intake attenuated the weight loss, fostered the preservation of intestinal architecture and integrity, and promoted survival in mice following infection with Salmonella Typhimurium. In addition, WpK4 modulated immune cellular response by inhibiting the production of pro-inflammatory cytokines and inducing anti-inflammatory mediators. These findings validate the probiotic properties of W. paramesenteroides WpK4 strain, and its eventual use in piglets. © 2015 Wageningen Academic Publishers.

Sandoval J.R.,Federal University of Minas Gerais | Sandoval J.R.,University of San Martin de Porres | Salazar-Granara A.,University of San Martin de Porres | Acosta O.,University of San Martin de Porres | And 5 more authors.
Journal of Human Genetics | Year: 2013

In order to investigate the underlying genetic structure and genomic ancestry proportions of Peruvian subpopulations, we analyzed 551 human samples of 25 localities from the Andean, Amazonian, and Coastal regions of Peru with a set of 40 ancestry informative insertion-deletion polymorphisms. Using genotypes of reference populations from different continents for comparison, our analysis indicated that populations from all 25 Peruvian locations had predominantly Amerindian genetic ancestry. Among populations from the Titicaca Lake islands of Taquile, Amantani, Anapia, and Uros, and the Yanque locality from the southern Peruvian Andes, there was no significant proportion of non-autochthonous genomes, indicating that their genetic background is effectively derived from the first settlers of South America. However, the Andean populations from San Marcos, Cajamarca, Characato and Chogo, and coastal populations from Lambayeque and Lima displayed a low but significant European ancestry proportion. Furthermore, Amazonian localities of Pucallpa, Lamas, Chachapoyas, and Andean localities of Ayacucho and Huancayo displayed intermediate levels of non-autochthonous ancestry, mostly from Europe. These results are in close agreement with the documented history of post-Columbian immigrations in Peru and with several reports suggesting a larger effective size of indigenous inhabitants during the formation of the current country's population. © 2013 The Japan Society of Human Genetics All rights reserved.

Santos V.R.D.,GENE Nucleo de Genetica Medica | Santos V.R.D.,Institute Criminalistica Of Minas Gerais | Pena H.B.,GENE Nucleo de Genetica Medica | Pena S.D.J.,GENE Nucleo de Genetica Medica | Pena S.D.J.,Federal University of Minas Gerais
Genetics and Molecular Research | Year: 2015

We have previously developed a panel of 40 insertion-deletion (INDEL) human DNA polymorphisms that was proven to adequately cover the span of global human genetic diversity. The panel was found to have very low matching probabilities with respect to both the global and Brazilian populations. To optimize the panel for application with degraded DNA samples, which are commonly encountered in forensic analysis, we have significantly reduced the amplicon size of the INDELs and developed a new multiplex panel. The panel has an amplicon size ranging from 50 to 153 base pairs, with a mean of 93 base pairs. It could be amplified by polymerase chain reaction in two multiplex reactions, which were then combined for electrophoretic separation and identification of the individual products in the ABI3130 four-color DNA analyzer. The results of the new panel were fully validated. © FUNPEC-RP.

Pena H.B.,GENE Nucleo de Genetica Medica | Pena S.D.J.,GENE Nucleo de Genetica Medica | Pena S.D.J.,Federal University of Minas Gerais
Transfusion Medicine and Hemotherapy | Year: 2012

Objective: Short insertion-deletion polymorphisms (indels) are the second most abundant form of genetic variations in humans after SNPs. Since indel alleles differ in size, they can be typed using the same methodological approaches and equipment currently utilized for microsatellite genotyping, which is already operational in forensic laboratories. We have previously shown that a panel of 40 carefully chosen indels has excellent potential for forensic identification, with combined probability of identity (match probability) of 7.09 × 10-17 for Europeans. Methods: We describe the successful development of a multiplex system for genotyping the 40-indel panel in long thin denaturing polyacrylamide gels with silver staining. We also demonstrate that the system can be easily fully automated with a simple large scanner and commercial software. Results and Conclusion: The great advantage of the new system of typing is its very low cost. The total price for laboratory equipment is less than EUR 10,000.-, and genotyping of an individual patient will cost less than EUR 10.- in supplies. Thus, the 40indel panel described here and the newly developed 'low-tech' analysis platform represent useful new tools for forensic identification and kinship analysis in laboratories with limited budgets, especially in developing countries. © 2012 S. Karger GmbH, Freiburg.

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