Centro de Estudos do Genoma Humano:
Seis Anos de Experiência no Diagnóstico Molecular da Síndrome de Rett
DOI:
https://doi.org/10.4181/RNC.2012.20.688.6pPalavras-chave:
Síndrome de Rett, Gene MECP2, Mutação, Técnicas de Diagnóstico MolecularResumo
Objetivo. A síndrome de Rett (RTT), causada por mutações no gene MECP2, é uma encefalopatia grave e a segunda causa mais frequente de retardo mental em meninas. O objetivo deste trabalho é avaliar a experiência do Centro de Estudos do Genoma Humano (CEGH) em seis anos de diagnóstico molecular da RTT. Método. Levantamento retrospectivo dos prontuários dos pacientes atendidos no CEGH com suspeita clínica de RTT entre 2005 e 2010. Resultados. Dois métodos de análise foram empregados: sequenciamento direto dos exons 3 e 4 do gene MECP2 ou triagem de mutações nos exons 2, 3 e 4 seguida de sequenciamento das amostras que tivessem alguma alteração detectada na triagem. Dos 139 probandos testados, encontramos a mutação patogênica em 59 (42,4%). Dessas, oito nunca haviam sido descritas. Ambos os métodos foram igualmente eficazes. Conclusões. Dada a variabilidade clínica de RTT, nossa taxa de detecção é compatível com a literatura para uma amostra contendo casos típicos e atípicos e para o método empregado. Concluímos que o sequenciamento direto é um método eficaz e que traz a vantagem adicional de ser capaz de detectar mutações novas. Para melhorar nossa taxa de detecção, passaremos a oferecer também o teste para grandes deleções em MECP2.
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Publicado: 2012-03-31
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