Guillermo Lay-Son1, Karena Espinoza2, Cecilia Vial2, Juan C Rivera2, María L Guzmán3, Gabriela M Repetto3. 1. Center for Human Genetics, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile; Hospital Padre Hurtado, Santiago, Chile. Electronic address: glayson@udd.cl. 2. Center for Human Genetics, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile. 3. Center for Human Genetics, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile; Hospital Padre Hurtado, Santiago, Chile.
Abstract
OBJECTIVES: Clinical use of microarray-based techniques for the analysis of many developmental disorders has emerged during the last decade. Thus, chromosomal microarray has been positioned as a first-tier test. This study reports the first experience in a Chilean cohort. METHODS: Chilean patients with developmental disabilities and congenital anomalies were studied with a high-density microarray (CytoScan™ HD Array, Affymetrix, Inc., Santa Clara, CA, USA). Patients had previous cytogenetic studies with either a normal result or a poorly characterized anomaly. RESULTS: This study tested 40 patients selected by two or more criteria, including: major congenital anomalies, facial dysmorphism, developmental delay, and intellectual disability. Copy number variants (CNVs) were found in 72.5% of patients, while a pathogenic CNV was found in 25% of patients and a CNV of uncertain clinical significance was found in 2.5% of patients. CONCLUSION: Chromosomal microarray analysis is a useful and powerful tool for diagnosis of developmental diseases, by allowing accurate diagnosis, improving the diagnosis rate, and discovering new etiologies. The higher cost is a limitation for widespread use in this setting.
OBJECTIVES: Clinical use of microarray-based techniques for the analysis of many developmental disorders has emerged during the last decade. Thus, chromosomal microarray has been positioned as a first-tier test. This study reports the first experience in a Chilean cohort. METHODS: Chilean patients with developmental disabilities and congenital anomalies were studied with a high-density microarray (CytoScan™ HD Array, Affymetrix, Inc., Santa Clara, CA, USA). Patients had previous cytogenetic studies with either a normal result or a poorly characterized anomaly. RESULTS: This study tested 40 patients selected by two or more criteria, including: major congenital anomalies, facial dysmorphism, developmental delay, and intellectual disability. Copy number variants (CNVs) were found in 72.5% of patients, while a pathogenic CNV was found in 25% of patients and a CNV of uncertain clinical significance was found in 2.5% of patients. CONCLUSION: Chromosomal microarray analysis is a useful and powerful tool for diagnosis of developmental diseases, by allowing accurate diagnosis, improving the diagnosis rate, and discovering new etiologies. The higher cost is a limitation for widespread use in this setting.
Keywords:
Anomalias congênitas; Atraso de desenvolvimento; Congenital anomalies; Copy number variants; Developmental disabilities; Diagnosis; Diagnóstico; Microarrays; Variante do número de cópia