Project description:An increasing number of genes involved in chromatin structure and epigenetic regulation has been implicated in a variety of developmental disorders, often including intellectual disability. By trio exome sequencing and subsequent mutational screening we now identified two de novo frameshift mutations and one de novo missense mutation in the CTCF gene in individuals with intellectual disability, microcephaly and growth retardation. Furthermore, a patient with a larger deletion including CTCF was identified. CTCF (CCCTC-binding factor) is one of the most important chromatin organizers in vertebrates and is involved in various chromatin regulation processes such as higher order of chromatin organization, enhancer function, and maintenance of three-dimensional chromatin structure. Transcriptome analyses in all three patients with point mutations revealed deregulation of genes involved in signal transduction and emphasized the role of CTCF in enhancer-driven expression of genes. Our findings indicate that haploinsufficiency of CTCF affects genomic interaction of enhancers and their regulated gene promoters that drive developmental processes and cognition. ChIP-seq analysis of CTCF genomic binding sites in lymphocytes of a control individual (no replicates).
Project description:An increasing number of genes involved in chromatin structure and epigenetic regulation has been implicated in a variety of developmental disorders, often including intellectual disability. By trio exome sequencing and subsequent mutational screening we now identified two de novo frameshift mutations and one de novo missense mutation in the CTCF gene in individuals with intellectual disability, microcephaly and growth retardation. Furthermore, a patient with a larger deletion including CTCF was identified. CTCF (CCCTC-binding factor) is one of the most important chromatin organizers in vertebrates and is involved in various chromatin regulation processes such as higher order of chromatin organization, enhancer function, and maintenance of three-dimensional chromatin structure. Transcriptome analyses in all three patients with point mutations revealed deregulation of genes involved in signal transduction and emphasized the role of CTCF in enhancer-driven expression of genes. Our findings indicate that haploinsufficiency of CTCF affects genomic interaction of enhancers and their regulated gene promoters that drive developmental processes and cognition. Comparison of lymphocyte gene expression between 3 de novo CTCF mutation patients and 8 controls (4 technical replicates each, no biological replicates).
Project description:Intellectual disability is a common condition that carries lifelong severe medical and developmental consequences. The causes of intellectual disability (ID) remain unknown for the majority of patients due to the extensive clinical and genetic heterogeneity of this disorder. De novo mutations may play an important role in ID as most individuals with ID present as isolated cases without family history and/or clear syndromic indication. In addition, the involvement of such mutations have recently been demonstrated in a small number of individuals with ID. Here we evaluate the diagnostic potential and role of de novo mutations in a cohort of 100 patients with ID of unknown cause using family-based exome sequencing. Single end short-read (50 bp) SOLiD 4 sequencing data for 300 individuals, constituting 100 patient-parent trios. For more details please read; http://www.nejm.org/doi/full/10.1056/NEJMoa1206524. Dataset is created by RUNMC (Radboud University, Nijmegen Medical Center), partner of Geuvadis consortium (http://www.geuvadis.org).
Project description:An increasing number of genes involved in chromatin structure and epigenetic regulation has been implicated in a variety of developmental disorders, often including intellectual disability. By trio exome sequencing and subsequent mutational screening we now identified two de novo frameshift mutations and one de novo missense mutation in the CTCF gene in individuals with intellectual disability, microcephaly and growth retardation. Furthermore, a patient with a larger deletion including CTCF was identified. CTCF (CCCTC-binding factor) is one of the most important chromatin organizers in vertebrates and is involved in various chromatin regulation processes such as higher order of chromatin organization, enhancer function, and maintenance of three-dimensional chromatin structure. Transcriptome analyses in all three patients with point mutations revealed deregulation of genes involved in signal transduction and emphasized the role of CTCF in enhancer-driven expression of genes. Our findings indicate that haploinsufficiency of CTCF affects genomic interaction of enhancers and their regulated gene promoters that drive developmental processes and cognition.
Project description:An increasing number of genes involved in chromatin structure and epigenetic regulation has been implicated in a variety of developmental disorders, often including intellectual disability. By trio exome sequencing and subsequent mutational screening we now identified two de novo frameshift mutations and one de novo missense mutation in the CTCF gene in individuals with intellectual disability, microcephaly and growth retardation. Furthermore, a patient with a larger deletion including CTCF was identified. CTCF (CCCTC-binding factor) is one of the most important chromatin organizers in vertebrates and is involved in various chromatin regulation processes such as higher order of chromatin organization, enhancer function, and maintenance of three-dimensional chromatin structure. Transcriptome analyses in all three patients with point mutations revealed deregulation of genes involved in signal transduction and emphasized the role of CTCF in enhancer-driven expression of genes. Our findings indicate that haploinsufficiency of CTCF affects genomic interaction of enhancers and their regulated gene promoters that drive developmental processes and cognition.
Project description:De novo mutated ADNP is a most prevalent gene driving syndromic autism with intellectual disability. Using droplet digital PCR and RNA sequencing we identified somatic mutations in ADNP and in other genes in the olfactory bulb and hipocampi of Alzheimer's disease (AD) patients.
Project description:Mammalian SWI/SNF complexes are multi-subunit chromatin remodeling complexes associated with an ATPase, either SMARCA4 or SMARCA2. Heterozygous mutations in the SMARCA2 ATPase cause Nicolaides-Baraitser Syndrome (NCBRS), an intellectual disability syndrome associated with delayed speech onset. We engineered human embryonic stem cells (hESCs) to carry NCBRS-associated heterozygous SMARCA2 K755R or R1159Q mutations. While SMARCA2 mutant hESCs were phenotypically normal, differentiation to neural progenitors cells (NPCs) was severely impaired. We find that SMARCA2 mutations cause enhancer reorganization with loss of SOX3-dependent neural enhancers and prominent emergence of astrocyte-specific de novo enhancers. Changes in chromatin accessibility at enhancers were associated with an increase in SMARCA2 binding and retargeting of SMARCA4. We show that AP-1 family member FRA2 is aberrantly overexpressed in SMARCA2 mutant NPCs, where it functions as a pioneer factor at de novo enhancers. Together, our results demonstrate SMARCA2 mutations cause impaired differentiation through enhancer reprogramming via inappropriate targeting of SMARCA4.
Project description:Intellectual disability is a common condition that carries lifelong severe medical and developmental consequences. The causes of intellectual disability (ID) remain unknown for the majority of patients due to the extensive clinical and genetic heterogeneity of this disorder. De novo mutations may play an important role in ID as most individuals with ID present as isolated cases without family history and/or clear syndromic indication. In addition, the involvement of such mutations have recently been demonstrated in a small number of individuals with ID. Here we evaluate the diagnostic potential and role of de novo mutations in a cohort of 100 patients with ID of unknown cause using family-based exome sequencing.