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The examination of copy number variation (CNV) is critical to understand the etiology of the CNV-related autism spectrum disorders (ASD). DNA samples were obtained from 64 ASD probands, which were genotyped on an Affymetrix CytoScan HD platform. qPCR or FISH were used as a validation for some novel recurrent CNVs. We further compared the clinical phenotypes of the genes in the Database of Chromosomal Imbalance and Phenotype in Humans Using Ensembl Resources (DECIPHER) database with these overlapping genes. Using vast, readily available databases with previously reported clinically relevant CNVs from human populations, the genes were evaluated using Enrichment Analysis and GO Slim Classification. By using the Ploysearch2 software, we identified the interaction relationship between significant genes and known ASD genes. A total of 29 CNVs, overlapping with 520 genes, including 315 OMIM genes, were identified. Additionally, myocyte enhancer factor 2 family (MEF2C) with two cases of CNV overlapping were also identified. Enrichment analysis showed that the 520 genes are most likely to be related to membrane components with protein-binding functions involved in metabolic processes. In the interaction network of those genes, the known ASD genes are mostly at the core position and the significant genes found in our samples are closely related to the known ASD genes. CNVs should be an independent factor to induce autism. With the strategy of our study, we could find the ASDs candidate genes by CNV data and review certain pathogenesis of this disorder. Those CNVs were associated with ASD and they may contribute to ASD by affecting the ASD-related genes.

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RESUMEN

Objective The aim of present study was to detect methylation rate of CpG unit of brain derived neurotrophic factor (BDNF) promoter and to study the epigenetic mechanism of autism spectrum disorders (ASD).Methods Total of 12 ASD patients and 12 healthy controls were recruited.The methylation rate of CpG unit in BDNF promoter Ⅰ and Ⅳ were detected using Sequenom MassArray method.The methylation model,correlationship,evolutionary relationship of CpG units in BDNF promoter Ⅰ and Ⅳ were detected and compared between ASD patients and healthy controls.Results The methylation rate was identified in 17 and 8 CpG units in BDNF promoter][and BDNF promoter Ⅳ.A close correlation distance was detected in BDNF promoter Ⅰ CpG units 4,7,10,35,and BDNF promoter Ⅳ CpG units 11.12,14.BDNF promoter][CpG units 4,7,10,35,and BDNF promoter Ⅳ CpG units 11.12,14 could be clustered.ASD patients had a significant lower methylation rate in BDNF promoter Ⅰ CpG unit 5.6 and Ⅳ CpG units 3 and 15 compare with healthy controls (P＜0.05).Conclusions The DNA methylation rate in BDNF pronoter Ⅰ CpG unit 5.6 and Ⅳ CpG units 3 and 15 may be used as potential biomarkers of ASD.