Retrospective karyotype study in mentally retarded patients

• Autor(a) principal: Teixeira,Wellcy Gonçalves
• Data de Publicação: 2016
• Outros Autores: Marques,Fabiana Kalina, Freire,Maíra Cristina Menezes
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Revista da Associação Médica Brasileira (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-42302016000300262
• topic: karyotype; intellectual disability; chromosome aberrations

SUMMARY Objective: To describe the chromosomal alterations in patients with mental retardation (MR) using G-banding karyotype analysis. Method: A retrospective study of the results G-banding karyotype analysis of 369 patients investigated for MR was performed. Based on the structural rearrangements found, the authors searched all chromosomal regions related with breakpoints, and these were compared with the literature on MR and databases. Results: 338 (91.6%) normal cases, and 31 (8.4%) with some type of chromosomal abnormality were identified. Among the altered cases, 21 patients (67.8%) were identified with structural chromosomal alterations, nine (29%) with numerical alterations, and one (3.2%) with numerical and structural alterations. Conclusion: Structural chromosomal abnormalities were observed more frequently in this study. G-banding karyotyping contributes to the investigation of the causes of MR, showing that this technique can be useful for initial screening of patients. However, higher resolution techniques such as array based comparative genomic hybridization (aCGH) and multiplex ligation-dependent probe amplification (MPLA) can detect submicroscopic alterations commonly associated with MR.