Copy number variations independently induce autism spectrum disorder

Abstract

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.