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Diagnóstico citogenético de pacientes com retardo mental idiopático Cytogenetic diagnosis of patients with idiopathic mental retardation

J Bras Patol Med Lab 01/2011; 48(1):33-39.

ABSTRACT O retardo mental é uma condição presente em 2% a 3% da população e mais da metade dos casos ainda são considerados idiopáticos. Sua etiologia é heterogênea e as anomalias cromossômicas têm importante contribuição. A aplicação de técnicas de citogenética clássica e de citogenética molecular tem permitido o diagnóstico preciso em muitos casos, proporcionando melhor acompanhamento clínico e aconselhamento genético. Este trabalho tem como objetivo informar sobre os principais exames atualmente disponíveis para a investigação de rearranjos cromossômicos em pacientes com retardo mental idiopático, incluindo cariótipo com bandeamento G, hibridação in situ fluorescente (FISH), cariotipagem espectral (SKy), amplificação de múltiplas sondas dependente de ligação (MLPA) e hibridação genômica comparativa em array (array-CGH). resumo unitermos Retardo mental Cariótipo FISH SKY MLPA Array-CGH abstract Mental retardation is a condition that affects 2%-3% of the population and more than half of the cases are still deemed idiopathic. Its etiology is heterogeneous and chromosome abnormalities play a significant role. The application of classical cytogenetic and molecular cytogenetic techniques has enabled accurate diagnosis in several cases, which allows better clinical monitoring and genetic counseling. This paper aims at informing about the major tests currently available to investigate chromosome abnormalities in patients with idiopathic mental retardation, including GTG-banded karyotyping, fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), multiplex ligation-dependent probe amplification (MLPA) and array-comparative genomic hybridization (array-CGH).

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May 16, 2014