Project description:10 patients with Intellectual Disability diagnosed with a clinically relevant copy number change, selected to assess the dection performance of alternative platforms.
Project description:Rare DNA copy-number variation (CNV) plays an important role in the underlying genetic etiology of autism and intellectual disability. Although large numbers of copy-number variants (CNVs) have been recently implicated in autism, most are large affecting many genes and specificity of these lesions with respect to classically defined autism as opposed to more broadly defined developmental delay is unclear. We exploited the repeat architecture of the genome to target smaller regions (n=1340 hotspots, median size 15 kbp) flanked by repetitive sequence among 2,240 autism simplex patients and a subset of unaffected parents.
Project description:10 patients with Intellectual Disability diagnosed with a clinically relevant copy number change, selected to assess the dection performance of alternative platforms. 10 Affymetrix arrays were performed according to the manufacturer's directions on DNA extracted from peripheral blood samples.
Project description:Ongoing studies using genomic microarrays and next-generation sequencing have demonstrated that the genetic contributions to cardiovascular diseases have been significantly ignored in the past. The aim of this study was to identify rare copy number variants in individuals with congenital pulmonary atresia (PA). Based on the hypothesis that rare structural variants encompassing key genes play an important role in heart development in PA patients, we performed high-resolution genome-wide microarrays for copy number variations (CNVs) in 82 PA patient-parent trios and 189 controls with an Illumina SNP array platform. CNVs were identified in 17/82 patients (20.7%), and eight of these CNVs (9.8%) are considered potentially pathogenic. Five de novo CNVs occurred at two known congenital heart disease (CHD) loci (16p13.1 and 22q11.2). Two de novo CNVs that may affect folate and vitamin B12 metabolism were identified for the first time. A de novo 1-Mb deletion at 17p13.2 may represent a rare genomic disorder that involves mild intellectual disability and associated facial features. high-resolution genome-wide microarrays for copy number variations (CNVs) in 82 PA patient-parent trios and 189 controls with an Illumina SNP array platform. Only 21 samples with potentially pathogenic CNVs are included in this records
Project description:Autism spectrum disorder (ASD) and mental retardation (MR) represent clinically distinct neurodevelopmental disorders with a complex genetic etiology. Using microarrays we identified de novo copy number variations in the SHANK2 synaptic scaffolding gene in two unrelated ASD and MR patients; DNA sequencing of SHANK2 revealed additional variants including a de novo nonsense mutation and 7 rare inherited changes. Our findings further link common genes between ASD and intellectual disability.
Project description:We previously showed that NUDT21-spanning copy-number variations (CNVs) are associated with intellectual disability (ID), and that NUDT21-encoded CFIm25 regulates the protein levels of at least one dose-sensitive, ID-associated protein: MeCP2 (Gennarino et al., 2015). However, the patients’ CNVs also spanned multiple other genes raising the possibility that loss or gain of these other genes caused their symptoms. To determine if reduced NUDT21 function alone is sufficient to cause disease, we generated Nudt21 heterozygous null mice to mimic the human state of reduced expression. We found that although these mice have 50% reduced Nudt21 mRNA, they only have 30% less of its cognate protein, CFIm25. Despite this partial protein-level compensation, the Nudt21+/- mice have learning deficits and cortical hyperexcitability. Further, to determine the molecular mechanism driving neural dysfunction, we partially inhibited NUDT21 in human embryonic stem cell-derived neurons to reduce CFIm25 by 30%. This reduction in CFIm25 was sufficient to induce misregulated alternative polyadenylation (APA) and protein levels in hundreds of genes, dozens of which are associated with intellectual disability and whose dysregulation is likely contributing to disease symptoms. Altogether, these results indicate that disruption of NUDT21-regulated APA events in the brain can cause intellectual disability.