Estudo molecular da doença de Huntington e correlações com as manifestações clínicas

• Autor(a) principal: Pereira, Lorraine Poltronieri
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/1974
• topic: Doença de Huntington; Expressão gênica; Diagnóstico clínico; Dineínas; Farmacologia Bioquímica e Molecular; 61

Huntington's disease (HD) is a progressive neurodegenerative disease that leads to motor, cognitive and mental impairment. It is caused by CAG (guanine-cytosine-adenine) trinucleotide repeat expansion in the huntingtin gene, resulting in a mutant form which causes brain damage. A previous study of our research group in an animal model for HD observed changes in gene expression related to dynein and dynactin responsible for cellular traffic and neuronal development. The aim of this study was to relate the molecular diagnosis with clinical manifestations of HD and analyze the expression of axonemal dynein heavy chain gene 6(DNAH6), dynein light chains Tctex-type 1 (DYNLT1) and dynactin 3 (DCTN3) in patients. Participants of this study were divided into control group (n = 12) and group with clinical diagnosis of HD (n = 25). The clinical diagnosis was made by the medical team Clinical Genetics Clinic of the University Hospital Cassiano Antonio de Moraes, UFES (HUCAM / UFES) through the Unified scale for assessment of Huntington's disease (UHDRS). The molecular diagnosis of HD was confirmed in 68% of selected patients. In this study, we observed a negative correlation between the CAG expansion and the age of onset of symptoms. The relationship of disease severity with the overall functional capacity (TCF), as well as motor impairment was statistically significant (p <0.05). The CAG expansion and impairment of motor function are reflected negatively on the independence of patients. There was decreased expression of the gene DNAH6 in HD patients compared to the control group, which was consistent with that seen in the expression of this gene in the striatum of animal model with HD. There was no change to the DYNTL1 and DCTN3 genes. In the study, we consider important the ratio of the molecular diagnosis with the clinical study of UHDRS scale essential to assess the rate of progression of the HD in patients. It also suggests that evaluating the expression of the gene DNAH6, is a possible blood marker for the early cellular changes that precede the clinical manifestations of HD.