Análisis clínico y molecular de una paciente con pentasomia del cromosoma x.

INTRODUCCIÓN.La Pentasomia del X (49,XXXXX) es una alteración cromosómica poco frecuente, que afecta a mujeres y fue descrita en 1963 por Kesaree y Wooley. Hasta la fecha se han reportado menos de 30 casos en la literatura. Se presenta un caso de pentasomia del cromosoma X, y mediante biología molecular se determino el origen materno de los cromosomas X adicionales.CASO CLÍNICO:Paciente de 28 meses, con talla baja proporcionada, braquicefalia, fascies característica, genitales externos femeninos con labios mayores hipoplásicos, braquidactilia, clinodactilia bilateral del quinto dedo, luxación de rodilla derecha, deformidad en varo.Se realizó cariotipo en sangre periférica que reportó un complemento cromosómico 49,XXXXX.MATERIALES Y MÉTODOS: Se realizó extracción de ADN y PCR para la amplificación de ocho microsatélites o STRs tetra y dinucleotídicos situados a lo largo del cromosoma X. Los productos amplificados se analizaron en el secuenciador ALF EXPRESS. Con la  información alélica se realizó la construcción del haplotipo y el análisis de dosis génica mediante la determinación del área bajo la curva. RESULTADOS Y DISCUSIÓN: El análisis de los 8 STRs realizados en la paciente y sus padres, permitió establecer que los cromosomas X extras corresponden a información alélica heredada de la madre. Se analizan los resultados y los eventos que se han documentado como relacionados con los fenómenos de no disyunción. CONCLUSIÓN: El origen de la doble no disyunción que generó la pentasomia es materna, en donde un ovulo tetrasómico, con cuatro copias de cromosoma X fue fecundado con un espermatozoide monosómico normal

Perda de heterozigosidade e identificação de portadoras de distrofia muscular de Duchenne: um caso familiar com evento de recombinação

La distrofia muscular de Duchenne y Becker (DMD/DMB) es una entidad de herencia recesiva ligada al cromosoma X que se presenta con debilidad muscular y es causada por mutaciones en el gen de la distrofina. La pérdida de heterocigocidad permite identificar a las mujeres portadoras de deleción en el gen de la distrofina mediante haplotipos. Objetivo: identificar mujeres portadoras en una familia con un paciente afectado de DMD mediante análisis de pérdida de heterocigocidad. Materiales y métodos: se analizaron nueve miembros de una familia con un afectado de DMD. Se hizo extracción de ADN y amplificación de diez STR del gen de la distrofina; se construyeron haplotipos, y se determinó el estado de portadora de deleción en dos de las seis mujeres analizadas, quienes mostraron pérdida de heterocigocidad de tres STR. Se establecieron algunos eventos de recombinación. Resultados: Dos de las seis mujeres analizadas, mostraron perdida de heterocigocidad en tres de los diez STR genotipificados, indicando su estado de portadora de deleción en este fragmento del gen de la Distrofina Con la segregación familiar de los haplotipos se establecieron eventos de recombinación. Conclusiones: mediante pérdida de heterocigocidad es posible establecer el estado de portadora de deleción en el gen de la distrofina con un 100% de certeza. La construcción de haplotipos identifica el cromosoma X portador de la deleción en familiares del caso índice. Se evidenció un evento de recombinación en una de las hermanas del afectado, lo que hace indeterminado su estado de portadora.Duchenne/Becker Muscular Dystrophy (DMD/BMD) is an X-linked recessive disease characterized by muscular weakness. It is caused by mutations on the dystrophin gen. Loss of heterozygosity allows us to identify female carriers of deletions on the dystrophin gen. Objective: identify female carriers in a family with a patient affected by DMD. Material and methods: nine family members and the affected child were analyzed using DNA extraction and posterior amplification of ten STRs on the dystrophin gen. Haplotypes were constructed and the carrier status determined in two of the six women analyzed due to loss of heterozygosity in three STRs. Additionally, we observed a recombination event. Conclusions: loss of heterozygosity allows us to establish with a certainty of 100% the carrier status of females with deletions on the dystrophin gen. By the construction of haplotypes we were able to identify the X chromosome with the deletion in two of the six women analyzed. We also determined a recombination event in one of the sisters of the affected child. These are described with a high frequency (12%). A possible origin for the mutation is a gonadal mosaicism in the maternal grandfather or in the mother of the affected child in a very early stage in embryogensis. This can be concluded using the analysis of haplotypes.A distrofia muscular de Duchenne e Becker (DMD/DMB) é uma entidade de herança recessiva ligada ao cromossoma X que se apresenta com debilidade muscular e é causada por mutações no gene da distrofia. A perda de heterozigosidade permite identificar às mulheres portadoras de deleção no gene da distrofina mediante haplótipos. Objetivo: identificar mulheres portadoras em uma família com um paciente afetado de DMD mediante análises de perda de heterozigosidade. Materiais e métodos: se analisaram nove membros de uma família com um afetado de DMD. De fez extração de ADN e amplificação de dez STR do gene da distrofina; construíram-se haplótipos, e determinou-se o estado de portadora de deleção em duas das seis mulheres analisadas, as quais mostraram perda de heterozigosidade de três STR. Estabeleceram-se alguns eventos de recombinação. Resultados: duas das seis mulheres analisadas mostraram perda de heterozigosidade em três dos dez STR genotipados, indicando seu estado de portadora de deleção neste fragmento do gene da distrofina. Com a segregação familiar dos haplótipos se estabeleceram eventos de recombinação. Conclusões: mediante perda de heterozigosidade é possível estabelecer o estado de portadora de deleção no gene da distrofina com um 100% de certeza. A construção de haplótipos identifica o cromossoma X portador da deleção em familiares do caso índice. Evidenciou-se um evento de recombinação em uma das irmãs do afetado, o que faz indeterminado seu estado de portadora

Correlação genótipo-fenótipo e análise molecular em pacientes com síndrome de Down

El síndrome Down (SD) es la trisomía más común en humanos, presentándose en 1 de cada 745 nacidos vivos y es la causa más frecuente de retardo mental. El origen más observado de la trisomíaes una no disyunción meiótica (95%), la cual generalmente es de origen materno, mientras un 5% se debe a errores post-cigóticos mitóticos. Objetivo: identificar el origen parental delcromosoma 21 extra, el momento del error no disyuncional y establecer una correlación entre estos eventos y las manifestaciones fenotípicas de los pacientes afectados. Materiales y métodos: se estudiaron cincuenta familias con un hijo con SD mediante el uso de cinco short tandem repeats (STR) a lo largo de 21q, se construyeron los haplotipos de cada paciente y sus padres, determinandoel origen parental y el momento en que surgió el error no disyuncional. Resultados:en 80% de las familias el error fue en meiosis I y 20% en la meiosis II; 98% de los cromosomasadicionales fue de origen materno y 2% paterno. Se encontró correlación genotipo-fenotipo en ocho características estudiadas: cuello corto y ancho, tercera fontanela, labio inferior prominente, paladar estrecho y corto, raíz del hélix cruzando la concha, alopecia, pliegue único palmar yotras anomalías como nevus y xeroderma y eventos de recombinación en 24,5% de las familias analizadas. Conclusiones: la edad materna y la variación en el número de recombinaciones está asociada con no disyunciones meióticas I y II; se encontró correlación entre el momento del errorno disyuncional y algunas variables clínicas.Down Syndrome (DS) is the most common trisomy in human beings. Its incidence is estimatedin one of 745 live births. On a global scale, it is the most frequent cause of mental retardation.The origin of this trisomy is due to a meiotic non-disjunction in about 95% of cases and is usuallymaternal, especially in women above 35 years of age. The remaining 5% is due to errors inpost-zygotic mitosis. Objective: identify the parental origin of the extra chromosome 21, whenthe error is not disyuncional and establish a correlation between these events and phenotypic manifestations of the patients affected. Materials and methods: we studied fifty families with achild with DS, using 5 STRs markers along 21q which allowed identification of the origin of chromosome 21 additional parents, the time when the error occurred and recombination presents. Thestatistical analysis was done using the package SPSS version 15.0 for Windows. Results: in 80% of households in the error was meiosis I and 20% in meiosis II, 98% of the additional chromosomes was home maternal and paternal 2% similar to those reported by other authors, correlation was found genotype-phenotype characteristics studied at 8, neck short and wide, third fontanel, prominent lower lip, palate narrow and short, crossing hélix root of the shell, alopecia, singlepalm crease and other anomalies as nevi and xeroderma and recombination events in 24,5% ofthe families tested. Conclusions: the maternal age and variation in the number of recombinationis not associated with disjunctions meiotics I and II genotype phenotype correlation was found, but the sample size should be expanded in order to establish with certainty that the correlations.O síndrome de Down (SD) é a trissomia mais comum em humanos, apresentando-se em 1 de cada745 nascidos vivos e é a causa mais frequentes de retardo mental. A origem mais observada datrissomia é uma não-disjunção meiótica (95%), a qual geralmente é de origem materna, enquantoum 5% se deve a erros pós-zigoticos mitóticos. Objetivo: identificar a origem parental do cromossoma 21 extra, o momento do erro não-disjuncional e estabelecer uma correlação entre esteseventos e as manifestações fenotípicas dos pacientes afetados. Materiais e métodos: se estudaram cinquenta famílias com um filho com SD mediante o uso de cinco short tandem repeats (STR) aolonge de 21q, se construíram os haplótipos de cada paciente e seus pais, determinando a origemparental e o momento em que surgiu o erro não-disjuncional. Resultados: em 80% das famíliaso erro foi em meiose I e 20% na meiose II; 98% dos cromossomas adicionais foi de origem maternoe 2% paterno. Encontrou-se correlação genótipo-fenótipo em oito características estudadas:pescoço curto e amplo, terceira fontanela, lábio inferior proeminente, paladar apertado e curto,raiz da hélix a través da concha, alopecia, prega palmar única e outras anomalias como nevus exeroderma e eventos de recombinação em 24,5% das famílias analisadas. Conclusões:a idade maternae a variação no número de recombinações está associada com não-disjunções meióticas I e II; encontrou-se correlação entre o momento do erro não disjuncional e algumas variáveis clínicas

The experience of Colombian boys and young men living with Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a chronic disease that primarily affects males and is characterized by progressive physical impairment and, eventually, death. This qualitative study aimed to explore and understand the experience of diagnosis and disease in young people with DMD living in Bogotá, Colombia. After securing approval from the Research Ethics Committee (CEI-ABN026-000311), nine individuals took part of a semi-structured interview, and their narratives were analyzed using thematic analysis. The main topics developed throughout the narratives were: negative representation of the disease; fear; difficulty expressing emotions; the patient-doctor relationship; the wheelchair; the caregivers and coping strategies. We conclude that young people affected by DMD face several challenging experiences that underscore the need for better, more respectful, and compassionate interactions with healthcare providers. Also, their experiences are indicative of a socio-cultural context that needs to become more responsive and compassionate towards young people and disability

A first description of the Colombian national registry for rare diseases

Objective: Orphan diseases must be considered a public health concern, underlying country-specific challenges for their accurate and opportune diagnosis, classification and management. Orphan disease registries have not yet been created in South America, a continent having a population of ~ 415 million inhabitants. In Colombia ~ 3 million of patients are affected by rare diseases. The aim of the present study was to establish the first Colombian national registry for rare diseases. The registry was created after the establishment of laws promoting the development of clinical guidelines for diagnosis, management, census and registry of patients suffering rare diseases. Results: In total, 13,215 patients were recorded in the Colombian registry. The survey reported 653 rare diseases. The most common diseases were congenital factor VIII deficiency (hemophilia A) (8.5%), myasthenia gravis (6.4%), von Willebrand disease (5.9%), short stature due to growth hormone qualitative anomaly (4.2%), bronchopulmonary dysplasia (3.9%) and cystic fibrosis (3.2%). Although, a marked under-reporting of cases was observed, some pathologies displayed similar behavior to that reported by other initiatives and databases. The data currently available in the registry provides a baseline for improvement regarding local and regional surveys and the start for better understanding rare diseases in Colombia. © 2017 The Author(s)

Analysis of Urine Samples for the Molecular Detection of Infectious Diseases. Application to the Identification of Human Cytomegalovirus

La implementación de metodologías de biología molecular como la reacción en cadena de la polimerasa (PCR), ha permitido la realización de diagnósticos sensibles y específicos para múltiples enfermedades, dentro de las cuales son de gran interés las infecciosas. Hasta hoy, los métodos de identificación se basan principalmente en cultivos y serología por su sensibilidad y especificidad, pero consumen tiempo y dinero. Las muestras de orina se han constituido en una alternativa no invasiva de obtención de ADN para la realización de análisis de biología molecular. Metodología: Implementación de una estrategia para la obtención de ADN a partir de muestras de orina. Las muestras fueron tomadas de niños de guardería, para documentar la presencia o no de inhibidores de PCR a través de la amplificación de genes de Citomegalovirus humano (CMVH). Resultados: En el 27,1% de las muestras analizadas se evidenció amplificación específica para CMVH, no se encontraron diferencias significativas en la presencia del virus en los tres estratos, pero sí en la intensidad de las bandas. Conclusión: Se verificó la ausencia de inhibidores de PCR mediante la amplificación del gen de la B-globina. Se estandarizó una metodología molecular para la identificación de CMVH, la cual puede ser aplicadaMolecular biology methods like Polimerase Chain Reaction (PCR) has been used for diagnosis of infectious diseases. Until today, the identification methods are based mainly on cultures and serology due to their sensibility and specificity, but they are expensive and time consuming. Urine samples constitute an alternative, noninvasive, method of obtaining DNA for the accomplishment of molecular Biology analysis. Methodology: implementation of a strategy to obtain DNA from urine samples. Samples were taken from children in daycare centers, to document the presence of inhibitors, PCR amplification of genes of human Cytomegalovirus (HCMV) was done. Results: In 27.1% of the analyzed samples, specific amplification for HCMV was demonstrated. No viral significant differences were found in the three layers, although it was present in the bands. Conclusion: The inhibitor absence was verified using PCR by amplificating the gene of the B-globine. A molecular methodology for the HCMV identification was standardized, which can be applied in prenatal diagnosis of congenital infection

Análisis de deleciones en 15 exones situados dentro y fuera del hot spot mutacional del gen de la distrofina en pacientes con distrofia muscular de Duchenne

Introducción. La distrofia muscular de Duchenne (DMD), y su forma alélica más leve, la distrofia muscular de Becker (DMB), es una entidad de herencia recesiva ligada al X, que se presenta con debilidad muscular, pérdida progresiva de las habilidades motoras y muerte precoz. Es causada principalmente por deleciones en el gen de la distrofina, el cual contiene 79 exones.Objetivo. Realizar un análisis ampliado para evaluar la presencia de deleciones en 15 exones del gen de la distrofina situados dentro y fuera del hot spot mutacional en 58 pacientes afectados con DMD/DMB sin mutación previamente identificada.Metodología. Amplificación, mediante PCR múltiplex, de 4 exones situados dentro y 11 fuera del hot spot mutacional descrito para el gen de la distrofina en 58 pacientes afectados con DMD y determinar la frecuencia de deleciones en la población analizada. Resultados. Se encontró deleción del exón 16 en uno de los pacientes estudiados, hecho que indica una frecuencia de 1,7%. No se observó ninguna deleción de los exones situados fuera del hot spot mutacional.Conclusiones. La frecuencia de deleciones en los 15 exones del gen de la distrofina analizados es baja; sólo se presentó en el exón 16, el cual se encuentra localizado en el hot spot mutacional proximal del gen. Es importante analizar este exón en los afectados, en la medida en que aumenta la tasa de detección de deleciones en un 1,7%. Se debe analizar otro tipo de mutaciones como puntuales y duplicaciones en los afectados.Introduction. Duchenne and Becker Muscular Dystrophies (DMD/DMB) are X-linked recessive diseases characterized by progressive muscle weakness and wasting, loss of motor skills and death after the second decade of life. Deletions are the most prevalent mutations that affect the dystrophin gene, which spans 79 exons.Objective: Identify deletions on the dystrophin gene in 58 patients affected with DMD.Methods: Through multiplex PCR identify deletions on the dystrophin gene in 58 patients with DMD and observe the frequency of this mutation in our population.Results: We found deletions in 1.72% of patients (1 of 58 persons). Deletions were not the principal cause of disease in our population. It is possible that duplications and point mutations caused this illness in our patients.Conclusions: The frequency of deletions in the 15 exons analyzed from the dystrophin gene was low. The predominant types of mutation in our patients` samples were not deletions as has been observed in the literature worldwide, therefore, it is important to determine other types of mutations as are duplications and point mutations

Absence of DEATH kinesin is fatal for Leishmania mexicana amastigotes

Kinesins are motor proteins present in organisms from protists to mammals playing important roles in cell division, intracellular organisation and flagellum formation and maintenance. Leishmania mexicana is a protozoan parasite of the order Kinetoplastida causing human cutaneous leishmaniasis. Kinetoplastida genome sequence analyses revealed a large number of kinesins showing sequence and structure homology to eukaryotic kinesins. Here, we investigate the L. mexicana kinesin LmxKIN29 (LmxM.29.0350), also called DEATH kinesin. The activated MAP kinase LmxMPK3, a kinase affecting flagellum length in Leishmania, is able to phosphorylate recombinant full length LmxKIN29 at serine 554. Insect promastigote LmxKIN29 Leishmania null mutants showed no obvious phenotype. However, in mouse infection experiments, the null mutants were unable to cause the disease, whereas LmxKIN29 add-backs and single allele knockouts caused footpad lesions. Localisation using promastigotes expressing GFP-tagged LmxKIN29 revealed that the kinesin is predominantly found in between the nucleus and the flagellar pocket, while in dividing cells the GFP-fusion protein was found at the anterior and posterior ends of the cells indicating a role in cytokinesis. The inability to cause lesions in infected animals and the amino acid sequence divergence from mammalian kinesins suggests that LmxKIN29 is a potential drug target against leishmaniasis

Disseminating and assessing implementation of the EULAR recommendations for patient education in inflammatory arthritis:a mixed-methods study with patients' perspectives

OBJECTIVES: To explore patients' agreement and reasons for agreement or disagreement with the EULAR recommendations for patient education (PE) for people with inflammatory arthritis (IA). METHODS: This mixed-method survey collected data using snowball sampling. The survey had been translated into 20 languages by local healthcare professionals, researchers and patient research partners. It explored the degree to which patients with IA agreed with each recommendation for PE (0=do not agree at all and 10=agree completely) and their rationale for their agreement level in free text questions. Descriptive statistics summarised participants' demographics and agreement levels. Qualitative content analysis was used to analyse the free text data. Sixteen subcategories were developed, describing the reasons for agreement or disagreement with the recommendations, which constituted the categories. RESULTS: The sample comprised 2779 participants (79% female), with a mean (SD) age 55.1 (13.1) years and disease duration 17.1 (13.3) years. Participants strongly agreed with most recommendations (median 10 (IQR: 9-10) for most recommendations). Reasons for agreement with the recommendations included the benefit of using PE to facilitate collaborative care and shared decision making, the value of flexible and tailored PE, and the value of gaining support from other patients. Reasons for disagreement included lack of resources for PE, not wanting information to be tailored by healthcare professionals and a reluctance to use telephone-based PE. CONCLUSION: The EULAR recommendations for PE have been disseminated among patients with IA. Overall, agreement levels were very high, suggesting that they reflect patients' preferences for engaging in collaborative clinical care and using PE to facilitate and supplement their own understanding of IA. Reasons for not completely agreeing with the recommendations can inform implementation strategies and education of healthcare professionals