Frequência de microdeleções e microduplicações em pacientes com deficiência intelectual e/ou malformações congênitas investigados através de MLPA.

Abstract

Recent molecular cytogenetics technologies, including MLPA (multiplex ligation-dependent probe amplification), can detect chromosomal abnormalities non-visualizated with conventional cytogenetics (karyotype), such as microdeletions e and microduplications, usually associated with phenotypes that include intellectual disability and congenital malformations. This study had aimed to investigate patients with those clinical features, without clear etiology, from the medical genetics service from University Hospital Alcides Carneiro, Paraíba, Brazil. Fifty two patients were evaluated with MLPA kits P064, P036 and P070. In 26,92% were detected pathogenic copy number variations (CNVs), including 4 (7,92%) Williams-Beuren Syndrome; 2 (3,85%) 22q11 Deletion Syndrome; and one case of each Cri-du-Chat, Prader-Willi, Smith-Magenis and Wolf-Hirshhorn syndromes. Plus, less well-known CNVs were found: 5q35 microduplication; 13q34 microdeletion; 22q13.33 microduplication; 3p26 microdeletion, 20p12.2 microduplication and 20p13 microduplication. In 69,23% the results were negative. The results demonstrate that MLPA is an efficient molecular genetic testing to detect chromosomal microdeletions and microduplications.