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OBJETIVOS: Determinar los grados de fuerza muscular y la relación que tienen con los subtipos del síndrome de Guillain Barré en los pacientes afectados desde el año 2009 al 2013 del Instituto Nacional de Ciencias Neurológicas. MATERIALES Y MÉTODOS: Estudio de tipo descriptivo, correlacional, retroprospectivo, transversal; se estudio a 31 pacientes que fueron afectados con el Síndrome del Guillain Barré entre los años 2009 al 2013 del Instituto Nacional de Ciencias Neurológicas entre los 20 a los 79 años de edad; se utilizó como instrumentos el test manual de exploración muscular o test de fuerza muscular manual y se relacionó la variable con el subtipo del Síndrome de Guillain Barré extraída de los datos de la historia clínica de los pacientes. RESULTADOS: Los resultados del cruce de las variables subtipo de Síndrome de Guillain Barré y los grados de Fuerza muscular (divididas en dos grupos: con alteración funcional o sin alteración funcional) por medio de tablas de contingencia con la utilización de las pruebas de Chi –cuadrado el grado de los significancia de p > 0,05, con lo cual no se p grados de Fuerza Muscular no podrán ser probadas. Se observaron que las alteraciones de los grados de fuerza muscular a nivel funcional están presenten a predominio de los grupos musculares de los segmentos distales, tanto de miembros superiores como miembros inferiores. CONCLUSIONES: No se pudo demostrar la relación entre los subtipos del Síndrome de Guillain Barré, las posibles causas de los resultados aún se mantienen en discusión para futuras investigaciones. Las alteraciones de los grados de fuerza muscular funcional son predominantes en los segmentos distales. / OBJECTIVES: To determine the degree of muscle strength and the relationship they have with the subtypes of Guillain Barre syndrome in patients affected from 2009 to 2013 of the Instituto Nacional de Ciencias Neurológicas. MATERIALS AND METHODS: Descriptive, correlational, retroprospective, transversal; 31 patients who were affected with Guillain Barre Syndrome from 2009 to 2013 of the Instituto Nacional de Ciencias Neurológicas, the age range is 20 to 79 years old; Manual muscle test was used as instruments and it was related with the subtype of Guillain Barré syndrome, that data was extracted from medical records of patients. RESULTS: The results from the intersection of variables subtype of Guillain Barré and degrees of muscular strength (divided into two groups: those with functional impairment or without functional impairment ) using contingency tables and using Chi -square test the significance level of p> 0.05 , I was not found a significant difference between between subtypes of Guillain Barre syndrome and degrees of muscle strength. It was found degrees of muscle strenght alteration at the functional level a of the distal muscle groups in the upper limbs and lower limbs. CONCLUSIONS: it was not found a significant correlation between between subtypes of Guillain Barré and degrees of muscle strength. The possible causes of the results still are found under discussion for future studies. Alterations in the levels of functional muscle strength are predominant in the distal segments. KEYBOARDS: Subtype Guillain Barre Syndrome, Muscular Strength, degree of functional muscle strength, muscle strength degree of functional impairment.

Background: Duchenne and Becker muscular dystrophies, collectively referred to as dystrophinopathies, are recessive X-linked disorders characterized by progressive muscle weakness and ultimately cardiac and respiratory failure. Immediate family members are often primary caregivers of individuals with a dystrophinopathy. Methods: We explored the impact of this role by inviting primary caregivers (n = 209) of males diagnosed with childhood-onset dystrophinopathy who were identified by the Muscular Dystrophy Surveillance, Tracking, and Research Network (MD STARnet) to complete a mailed questionnaire measuring perceived social support and stress, spirituality, and family quality of life (FQoL). Bivariate and multivariate analyses examined associations between study variables using the Double ABCX model as an analytic framework. Results: Higher stressor pile-up was associated with lower perceived social support (r = -0.29, p <.001), availability of supportive family (r = -0.30, p <.001) or non-family (r = -0.19, p <.01) relationships, and higher perceived stress (r = 0.33, p <.001); but not with spirituality (r = -0.14, p > 0.05). FQoL was positively associated with all support measures (correlations ranged from: 0.25 to 0.58, p-values 0.01-0.001) and negatively associated with perceived stress and control (r = -0.49, p <.001). The association between stressor pile-up and FQoL was completely mediated through global perceived social support, supportive family relationships, and perceived stress and control; supportive non-family relationships did not remain statistically significant after controlling for other mediators. Conclusions: Findings suggest caregiver adaptation to a dystrophinopathy diagnosis can be optimized by increased perceived control, supporting family resources, and creation of a healthy family identity. Our findings will help identify areas for family intervention and guide clinicians in identifying resources that minimize stress and maximize family adaptation.

A distrofia muscular de cintura 2B (LGMD2B) é uma doença neuromuscular causada pela redução ou ausência da proteína sarcolemal disferlina. A disferlina está envolvida no reparo de membrana por atuar no tráfego e fusão de vesículas após estresse mecânico e, quando deficiente, as alterações nesta via levam à degeneração progressiva e irreversível das fibras musculares. A disferlina também tem sido implicada na inflamação e na miogênese durante a degeneração e regeneração muscular. Recentemente, identificou-se um tricomplexo formado pela disferlina com duas proteínas citoplasmáticas, FAM65B e HDAC6, no início da diferenciação de mioblastos. Investigar a regulação destas interações é importante para avançar na compreensão das funções da disferlina e seu papel na função muscular. Neste estudo, a miogênese e o reparo muscular foram investigados in vivo e in vitro em modelos com deficiência de disferlina. Para estudar o processo regenerativo in vivo, utilizamos um modelo de eletroporação para induzir degeneração/regeneração no músculo distrófico levemente afetado do camundongo disferlina-deficiente SJL/J. A avaliação histopatológica e a expressão relativa dos genes Pax7, Myf5, MyoD e miogenina foram acompanhadas durante a recuperação muscular em diferentes tempos após a lesão. Além disso, investigamos os efeitos da deficiência de disferlina na expressão dos genes Fam65b e Hdac6. Observamos um curso de tempo alterado do processo de degeneração e regeneração, com notável capacidade regenerativa nos camundongos disferlina-deficientes, caracterizada por uma resposta mais rápida e eficaz nos primeiros dias após a lesão, em comparação com os camundongos normais. Além disso, Fam65b e Hdac6 foram ativados nos estágios iniciais da regeneração muscular, também com expressão mais elevada de ambos os genes no camundongo SJL/J. Esses resultados podem estar relacionados à uma possível condição pré-ativada do processo regenerativo no músculo de camundongos distróficos jovens. Para os experimentos in vitro, utilizamos células musculares humanas de pacientes com LGMD2B, com deficiência total de disferlina. A diferenciação muscular induziu a formação de miotubos mais finos e com menor frequência de núcleos por miotubo, sugerindo uma progressão retardada da formação de miotubos em células com LGMD2B. A expressão de mRNA de MYOD e FAM65B não foi aparentemente afetada pela deficiência de disferlina durante a diferenciação, enquanto HDAC6 apresentou um pico transitório após 24 horas, apenas nas células normais. Além disso, o pico da miogenina ocorreu mais cedo nas células normais. Portanto, sugerimos que a disferlina estaria menos envolvida nos eventos iniciais de formação de pequenos miotubos, mas poderia desempenhar um papel importante nos estágios posteriores de diferenciação, que envolvem crescimento e alongamento de miotubos. Estes resultados fornecem dados interessantes para investigações adicionais de como a deficiência de disferlina afeta os reguladores miogênicos durante a diferenciação. Em conjunto, nossos dados sugerem que a deficiência de disferlina provoca alterações temporais na progressão dos eventos de regeneração muscular e de miogênese. A identificação de uma possível regulação dos componentes do tricomplexo pela disferlina pode indicar novas direções para investigar esta via como um potencial alvo para terapias / Limb girdle muscular dystrophy 2B (LGMD2B) is a neuromuscular disease caused by reduction or absence of the sarcolemmal protein dysferlin. Dysferlin is involved in membrane repair by acting on vesicular traffic and fusion after mechanical stress and, when deficient, changes in this pathway lead to progressive and irreversible degeneration of muscle fibers. Dysferlin has also been implicated in inflammation and myogenesis during muscle degeneration and regeneration. Recently, a tricomplex formed by dysferlin with two cytoplasmic proteins, FAM65B and HDAC6, was identified at the earlier stages of myoblast differentiation. Investigating the regulation of these interactions is important to advance in the understanding of the functions of dysferlin and its role in muscle function. In this study, myogenesis and muscle repair were investigated in vivo and in vitro in models with dysferlin deficiency. To study this effect in the regenerative process of muscle in vivo, we used a model of electroporation inducing muscle degeneration/regeneration in the mildly affected dystrophic muscle of dysferlin-deficient SJL/J mouse. The histopathological evaluation and the relative expression of the genes Pax7, Myf5, MyoD and myogenin were accompanied during muscle recovery at different time points after injury. In addition, we investigated the effects of dysferlin deficiency in the expression of genes Fam65b and Hdac6. We observed an altered time course of the degeneration and regeneration process, with remarkable regenerative capacity in dysferlin-deficient mice, characterized by a faster and effective response in the first days after injury, as compared to normal mice. Moreover, Fam65b and Hdac6 were activated at the early stages of muscle regeneration, also with higher expression of both genes in the SJL/J mouse. These results may have been due to a possible pre-activated condition of the regenerative process in the muscle of young dystrophic mice. For the in vitro experiments, we used human muscle cells from patients with LGMD2B, with total deficiency of dysferlin. The muscular differentiation induced the formation of thinner myotubes and reduced frequency of myonuclei per myotube, suggesting a delayed progression of myotube formation in LGMD2B cells. mRNA expression of MYOD and FAM65B was not apparently affected by dysferlin deficiency during differentiation, while HDAC6 exhibited a transient peak, only in healthy cells, after 24 hours. In addition, the myogenin peak occurred earlier in healthy cells. Thus, we suggested that dysferlin would be less involved in the first events of formation of early small myotubes, but could play an important role in the later stages of differentiation, which involves myotube growth and elongation. These results provide interesting data for further investigation of how dysferlin deficiency affects myogenic regulators during differentiation. Taken together, our data suggest that dysferlin deficiency causes temporal changes in the progression of the muscle regeneration and myogenesis events. The identification of possible regulation of tricomplex components by dysferlin may indicate new directions for investigating this pathway as a potential target for therapies

Objetivo: Construir Escala de Avaliação Funcional do Sentar e Levantar do Solo para Portadores de DMD (EAF-2) e testar sua confiabilidade intra e interexaminadores. Método: A construção da escala ocorreu em etapas: 1. Análise do movimento de sentar e levantar do solo em crianças saudáveis. 2. Análise do movimento de sentar e levantar do solo em crianças com DMD. 3. Elaboração da primeira versão da escala e do manual de instrução. 4. Avaliação por peritos e reajustes gerando a versão final. 5. Análise de confiabilidade inter e intraexaminador e correlação com a Escala de Vignos, idade e tempo de execução da atividade. Resultados: A escala abrange três fases para o sentar e cinco para o levantar, cada fase contendo itens que devem ser avaliados e pontuados. O escore pode variar de 0 a 10 para o sentar e de 0 a 15 para o levantar. Foi demonstrado muito boa repetibilidade da medida do sentar e levantar (ICC = 0,89 e 084, respectivamente) e excelente reprodutibilidade (ICC = 0,93 e 0,92, respectivamente). O Coeficiente Kappa para as 8 fases na análise interexaminadores variou de 0,77 a 1,00 (confiabilidade excelente para 5 fases e substancial para 3 fases), e na análise intra-examinador variou de 0,80 a 1,00 (confiabilidade excelente para 6 fases e substancial para 2 fases). Encontrou-se boa correlação entre as variáveis idade x Escala de Vignos (r= 0,58) e levantar x Escala de Vignos (r= 0,56), enquanto que nas variáveis restantes a correlação foi baixa.Conclusão: A EAF-2 é um instrumento de avaliação confiável que permite avaliar a atividade de sentar e levantar em portadores de DMD de forma detalhada e operacionalizada. / Objective: Construct the Scale of Functional Evaluation of Sit-and-Stand from the Ground for Patients with DMD (EAF-2) and to test its reliability intra and interexaminer. Method: The construction of the scale occurred in stages: 1. Analysis of the movement to sit and stand from the ground in healthy children. 2. Analysis of the movement to sit and stand from the ground in children with DMD. 3. Elaboration of the first version of the scale and the manual of instruction. 4. Evaluation by experts and readjustments generating the final version. 5. Analysis of Reliability inter and intra-examiner and correlation with the Vignos Scale, age and time length for the execution of the activity. Results: The scale comprehends three phases for the sitting and five for the standing, each phase with items that must be evaluated and scored. The score may vary from 0 to 10 for the sitting and from 0 to 15 for the standing. A very good repeatability of the measure of sitting as well as of standing was demonstrated (ICC = 0,89 and 084, respectively) and excellent reproducibility (ICC = 0,93 and 0,92, respectively). The Kappa Coefficient for the 8 phases in the interexaminer analysis varied from 0,77 to 1,00 (excellent reliability for 5 phases and substantial for 3 phases), and in the intra-examiner analysis varied from 0,80 to 1,00 (excellent reliability for 6 phases and substantial for 2 phases). Good correlation was found between the variable age x Vignos Scale (r= 0,58) and to stand x Vignos Scale (r= 0,56), whereas in the remaining variable the correlation was low. Conclusion: The EAF-2 is a trustful instrument of evaluation that allows to evaluate the activity of sitting and standing in people with DMD in a detailed and operationalized way.

A Distrofia Muscular de Duchenne (DMD) é uma importante e severa doença músculo degenerativa causada pela mutação do gene da distrofina. Na ausência da distrofina, o sarcolema das células torna-se vulnerável devido a danos induzidos por ciclos contínuos de degeneração e regeneração. Consequentemente, a força muscular diminui e as miofibras são substituídas por tecido fibrótico. Dentre os músculos esqueléticos afetados, o diafragma, destaca-se por ser o principal músculo respiratório acometido na DMD. Similarmente a DMD humana, o modelo mdx, apesar de exibir um fenótipo suave, este apresenta um severo acometimento no músculo diafragma, assim como observado em nosso estudo prévio, aqui descritos. Entretanto, este é considerado um modelo pobre, porque ele não consegue reproduzir, o fenótipo severo observado nos pacientes. O camundongo mdx/utrn+/- (dystrophin-null heterozygous urtrophin mice) com haploinsuficiência da utrofina, tem sido hipotetizado como um modelo com um fenótipo intermediário, ganhando popularidade nos laboratórios. Porém, infelizmente, até os dias de hoje, não existe evidências fisiológicas e funcionais suficientes que justifiquem a escolha deste modelo para as terapias experimentais. Portanto, neste estudo objetivou-se esclarecer a real contribuição do camundongo mdx/utrn+/- para as terapias experimentais. Para testar esta hipótese, elegeu-se analisar a morfologia e a função muscular do músculo diafragma do mdx e mdx/utrn+/- com 2 e 6 meses de idade. Para elucidar a morfopatologia do diafragma foi utilizado microscopia de luz e análises de imunohistoquímica. A função muscular do diafragma foi analisada através da avaliação das propriedades contráteis e passivas. A forma de como executar a função muscular do diafragma foi atualizada através da criação de dois clips, os quais permitiram avaliar o músculo de forma segura. A adaptação de um novo protocolo de avaliação da função muscular mostrou-se eficaz e capaz de ser utilizada para avaliar as propriedades contráteis e passivas. Aos 2 meses de idade, as colorações de Hematoxilina e eosina, Tricômio de Masson e Alizarina vermelha revelaram que o mdx/utrn+ apresentou maior quantidade de infiltrado inflamatório, tecido conectivo e áreas de calcificação do que o mdx. Já aos 6 meses de idade, não houve diferença morfológica entre o mdx e o mdx/utrn+/-. Na análise de imunohistoquímica para eMyHC (miosina embrionária de cadeia pesada eMyHC), não foi observada diferença entre o mdx e o mdx/utrn+/-aos 2 e 6 meses de idade. Entretanto, os resultados obtidos em ambas as idades, demonstraram a presença de regeneração muscular. Na marcação da proteína distrofina e utrofina, as células inflamatórias e os tipos de fibras musculares também foram detectados por imunohistoquímicas. A marcação da proteína distrofina, mostrou-se ausente no mdx e mdx/utrn+/- com 2 e 6 meses de idade. A marcação da proteína utrofina mostrou-se mais evidente no mdx do que no mdx/utrn+/-, videnciando a haploinsuficiência nos mdx/utrn+/-. Macrófagos foram encontrados em maior quantidade no camundongo mdx/utrn+/- com 2 e 6 meses do que no mdx, mostrando que o processo de inflamação encontrou-se aumentado nos mdx/utrn+/- Neutrófilos encontraram-se aumentados no mdx/utrn+/- com 2 meses, evidenciando a fase aguda da inflamação. Entretanto nos animais de 6 meses, quantidades semelhantes de neutrófilos foram detectadas no mdx/utrn+/- e mdx. Fibras marcadas pelas isoformas MyHC- I, IIa e IIx foram detectadas em maior porcentagem no BL10 do que no mdx e mdx/utrn+/- aos 2 meses de idade, demonstrando que a diminuição destas, no mdx e mdx/utrn+/- pode colaborar para a diminuição da força nestes animais. Aos 6 meses, porcentagem similares de MyHC- I foram detectadas no BL10, mdx e mdx/utrn+/-. MyHC-IIa não foram encontradas nos animais de 6 meses. MyHC-IIx encontraram-se em maior porcentagem no BL10 do que no mdx e mdx/utrn+/- com 6 meses de idade. Baixa porcentagem de isoformas de MyHC- I/IIa foram detectadas no mdx e mdx/utrn+/- aos 2 e 6 meses de idade e encontraram-se ausentes no BL10 de mesma idade. Fibras marcadas pela isoformas MyHC-IIa/IIx apresentaram-se aumentadas no mdx e mdx/utrn+/- aos 2 e 6 meses, podendo este aumento auxiliar na manutenção da força muscular. MyHC-IIx-IIb foram detectadas em maior porcentagem no mdx, reduzidas no BL10 e ausentes no mdx/utrn+/- com 2 meses de idade. Estas não foram identificadas nos animais de 6 meses. As propriedades contráteis do camundongo mdx/utrn+/- aos 2 meses de idade apresentaram-se mais comprometidas do que no mdx. Pt (contração isométrica máxima), sPt (força específica de Pt), Po (Força tetânica máxima) e sPo (força específica de Po) exibiram-se mais afetadas no mdx/utrn+/- do que no mdx. Porém aos 6 meses de idade não houve diferença significativa de força entre o mdx/utrn+/- e o mdx. As propriedades passivas do mdx/utrn+/- com 2 meses apresentou mais acometida do que no mdx. Entretanto, aos 6 meses, esta propriedade não se diferenciou entre o mdx/utrn+/- e o mdx. Em suma, conclui-se que o mdx/utrn+/- representa um modelo superior ao mdx com 2 meses de idade, uma vez que este apresentou morfologia, propriedades contráteis e passiva mais comprometidas do que no mdx. Aos 6 meses as propriedades contráteis e passivas e morfológicas do camundongo mdx/utrn+/- não se diferenciou do mdx. Sugerimos que o uso do mdx/utrn+/- com 2 meses de idade pode potencializar os testes pré-clinicos / Duchenne Muscular Dystrophy (DMD) is an important and severe muscle wasting disease caused by a dystrophin mutation. In the absence of dystrophin, sarcolemma becomes vulnerable to damage due a damage caused by continuous cycles of degeneration regeneration. Consequently, the muscle force reduces and the myofibers are replaced by fibrotic tissue. Between the skeletal muscles, the diaphragm is main affected muscle in DMD. Similarly, to a human DMD, despite the mdx model exhibit a milder phenotype, he presents the diaphragm muscle severely affected, as it was observed in our previous study, here described. However, it is also considered a poor model because it cannot reproduce the severe dystrophic phenotype seen in patients. An utrophin heterozygous utrophin mice (mdx/utrn+/- ), has been hypothesized as an intermediate model and they are gaining popularity in many laboratories. However unfortunately there is currently, no physiological enough evidence to justify the choice of this model for experimental therapies. Therefore, in this study, we aimed to elucidate the real contribution of the mdx/utrn+/- for the experimental therapies. To test this hypothesis, we evaluated the diaphragm muscle morphology and muscle function of the mdx and mdx/utrn+/- with 2 and 6 months. To elucidate the diaphragm morphology, we used light microscopy techniques and immunostaining analysis. Muscle function was evaluated through the active and passive properties. The clamps allowed to safe evaluate the diaphragm function. The update of the new protocol was efficient and able to evaluate the active and passive properties. At 2 months, the Hematoxylin and eosin, Masson Thrichome, Alisarine red, revealed that the mdx/utrn+ showed more inflammatory infiltrate, connective tissue and more areas with calcification than mdx model. At 6 months, there was no significant differences between mdx and mdx/utrn+. In the immunohistochemical analysis for eMyHC (embryonic myosin heavy chain), there was no difference between mdx and mdx/utrn+/- at 2 and 6 months. However, the results obtained in both ages, showed muscle regeneration Marking for dystrophin and utrophin protein, inflammatory cells and fiber type were also detected by immunohistochemistry. Marking for dystrophin was absent in mdx and mdx/utrn+/- with 2 and 6 months. Marking for utrophin protein was more evident in mdx than in mdx/utrn+/- mice, evidencing the utrophin haploinsufficiency in mdx/utr+/-. Macrophages were increased in mdx/utrn+/- than in mdx mice with 2 and 6 months, showing an inflammation. Neutrophils were increased in mdx/utrn+/- at 2 month-old, evidencing the acute phase of inflammation. However, at 6 months similar amounts of neutrophil were detected in mdx and mdx/utrn+/-. Fibers marked by MyHC-I, IIa and IIx were detected in a higher percentage in BL10 than in mdx and mdx/utrn+/- at 2 months, showing that this change could collaborate with force decrease in these animals. At 6 months, similar percentage of MyHC-I was detected in BL10, mdx and mdx/utrn+/-. MyHC-IIa animals were not found at 6 months. Higher percentage of MyHC-IIx was found in BL10 than in mdx and mdx/utrn+/- with 6 months. Low percentage of MyHC- I/IIa was detected in mdx and mdx/utrn+/- at 2 and 6 months and it was absent in BL10 in the same age. Fibers marked by MyHC-IIa/IIx isoforms were increased in mdx and mdx/utrn+/- with 2 and 6 months. These changes could help to maintain the muscle force. MyHC-IIx-IIb was detected in higher percentage in mdx, reduced the BL10 and it was absent in mdx/utrn+/- with 2 months. MyHC-IIx-IIb was not identified in the animals with 6 months. Contractile properties in mdx/utrn+/- at 2 months were more affected than in mdx mice. Pt (maximal twitch force), sPt (specific twitch force), Po (maximal tetanic force) and sPo (specific tetanic force) showed more severely affected in mdx/utrn+/- than in mdx mice. At 6 months there were no significant difference in Pt, sPt, Po and sPo between mdx/utrn+/- and mdx mice. Passive properties of mdx/utrn+/- with 2 months presented more affected than the in mdx mice. However, at 6 months, this property did not differ between mdx/utrn+/- and mdx mice. In summary, we concluded that the mdx/utrn+/- at 2 month represent a superior model than the mdx with matched-age, since they presented morphology and contractile and passive properties more compromised than mdx mice. At 6 months, the mdx/utrn+/-contractile and the passive properties and morphology did not differ from the mdx mice age-matched. We suggest that the use of mdx/utrn+/- with 2 months-old would represent would represent a better model to test the potential of the therapies than mdx mice

Duchenne and Becker muscular dystrophies (DMD, BMD) are allelic X-linked diseases which affect approximately one in 3500 male newborns. They are caused by mutations in a gene positioned on the short arm of the X chromosome at Xp21. The first indication of the location of this gene was the description of rare females expressing DMD and who were found to have constitutional X;autosome translocations with an X chromosome breakpoint at this site. There are now 24 such females known worldwide. They express DMD as a consequence of preferential inactivation of the normal X chromosome. In order to contribute to the understanding of the aetiology of mutations causing DMD and the aetiology of constitutional translocations, two types of study have been performed here. Firstly, the detailed mapping of the X chromosome breakpoints of DMD-associated X;autosome translocations has been investigated. The results of this study have been compared with data on the physical distribution of mutations causing DMD in male patients. Secondly, one translocation, an X;l translocation with an autosomal breakpoint at Ip34, has been selected for more detailed investigation and the DNA sequence has been determined at the site of the rearrangement. Translocation breakpoint mapping studies were performed by somatic cell hybrid analysis. Hybrids were karyotyped and this information was used to construct a hybrid panel for the purpose of determining the autosomal localisations of anonymous DNA probes. The mapping of seven probes using this panel is described. The work described in this thesis revealed that the distribution of translocation breakpoints within the DMD gene appears to be random and may differ from the distribution of mutations in male patients. The X;l translocation whose breakpoints are cloned and sequenced was found to involve two expressed loci, one coding for dystrophin on the X chromosome and one for the leukocyte antigen related protein on chromosome 1. Sequence data revealed that a deletion of four to seven nucleotides from the X chromosome and a duplication of two to five nucleotides are associated with the translocation. The possible involvement of trinucleotides adjacent to the breakpoints, and of a LINE, a SINE and a stretch of potential Z-DNA within 1 kb of the X chromosome or the chromosome 1 breakpoint, is discussed.

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on March 25, 2010). Vita. Thesis advisor: Christian Lorson. "July 2009" Includes bibliographical references.

Thesis (M.F.A.)--Rochester Institute of Technology, 1995. / Typescript. Includes bibliographical references (leaves 30-31).

Thesis (Ph. D.)--University of Missouri--Columbia, 2004. / "December 2004" Typescript. Vita. Includes bibliographical references (l. 180-210). Also issued on the Internet.