Project description:Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders with high heritability. Recent findings support a highly heterogeneous and complex genetic etiology including rare de novo and inherited mutations or chromosomal rearrangements as well as double or multiple hits. We performed whole-exome sequencing (WES) and blood cell transcriptome by RNAseq in a subset of male patients with idiopathic ASD (n = 36) in order to identify causative genes, transcriptomic alterations, and susceptibility variants. We detected likely monogenic causes in seven cases: five de novo (SCN2A, MED13L, KCNV1, CUL3, and PTEN) and two inherited X-linked variants (MAOA and CDKL5). Transcriptomic analyses allowed the identification of intronic causative mutations missed by the usual filtering of WES and revealed functional consequences of some rare mutations. These included aberrant transcripts (PTEN, POLR3C), deregulated expression in 1.7% of mutated genes (that is, SEMA6B, MECP2, ANK3, CREBBP), allele-specific expression (FUS, MTOR, TAF1C), and non-sense-mediated decay (RIT1, ALG9). The analysis of rare inherited variants showed enrichment in relevant pathways such as the PI3K-Akt signaling and the axon guidance. Integrative analysis of WES and blood RNAseq data has proven to be an efficient strategy to identify likely monogenic forms of ASD (19% in our cohort), as well as additional rare inherited mutations that can contribute to ASD risk in a multifactorial manner. Blood transcriptomic data, besides validating 88% of expressed variants, allowed the identification of missed intronic mutations and revealed functional correlations of genetic variants, including changes in splicing, expression levels, and allelic expression.
Project description:MicroRNA expression levels in the lymphoblastic cells of prostate cancer patients and their healthy brothers from HPCX1 linked prostate cancer families were analyzed to trace variants that might alter miRNA expression and explain partly an inherited genetic predisposion to prostate cancer.
Project description:Despite inheritance of hypertension in families, identifying genetic mechanisms predisposing individuals to hypertension has remained challenging. The effects of single genes contributing to the development of hypertension may not be readily detected in individuals whose genomes also contain other genetic factors that resist hypertension. By using a highly permissive rat genome for inherited hypertension, we demonstrate that increased expression of one such gene, Rififylin (Rffl), is a novel inherited risk factor for hypertension and increased mortality. Animals overexpressing Rffl demonstrated delayed endocytic recycling, accumulated polyubiquitinated proteins, increased beats/min of neonatal cardiomyocytes, had shorter QT-intervals and developed salt-insensitive hypertension very early in their life (50-52 days). Thus, the discovery of a physiological link between overexpression of rififylin and the development of hypertension constitutes a novel mechanism that could be targeted for rectifying normal QT-interval and preventing hypertension.
Project description:Although the evidence for a genetic predisposition to human essential hypertension is compelling, the genetic control of blood pressure (BP) is poorly understood. The Dahl salt-sensitive (S) rat is a model for studying the genetic component of BP. Using this model we previously reported the identification of 16 different genomic regions that contain one or more BP quantitative trait loci (QTLs). The proximal region of rat chromosome 1 contains multiple BP QTLs. Of these, we have localized the BP QTL1b region to a 13.5cM (20Mb) region. Interestingly, five additional independent studies in rats and four independent studies in humans have reported genetic linkage for BP control by regions homologous to QTL1b. To view the overall renal transcriptional topography of the positional candidate genes for this QTL, we sought a comparative gene expression profiling between a congenic strain containing QTL1b and control S rats by employing: (1) a saturated QTL1b interval specific oligonucleotide array, and (2) a whole genome cDNA microarray representing 20,465 unique genes that are positioned outside the QTL. Results indicated that 19 out of the 231 positional candidate genes for this QTL are differentially expressed between the two strains tested. Surprisingly, over 1,500 genes outside of QTL1b were differentially expressed between the two rat strains. Integrating the results from the two approaches revealed at least one complex network of transcriptional control initiated by the positional candidate Nr2f2. This network appears to account for the majority of gene expression differences occurring outside of the QTL interval. Further substitution mapping is currently underway to test the validity of each of these differentially expressed positional candidate genes. These results demonstrate the importance of using a saturated oligonucleotide array for identifying and prioritizing differentially expressed positional candidate genes of a BP QTL. Keywords: : rat, hypertension, genetics, polygenic trait, microarray, gene expression
Project description:Single nucleotide variants (SNVs) in regulatory DNA are linked to inherited cancer risk. Massively parallel reporter assays (MPRA) of 5,031 SNVs linked to 14 neoplasms comprising >90% of human malignancies were performed in pertinent diploid cell types then integrated with matching chromatin accessibility, looping, and eQTL data to identify 411 regulatory SNVs and their putative target eGenes. The latter highlighted specific protein networks in lifetime cancer risk, including mitochondrial translation, proliferation, signaling, adhesion, and immunity. This cancer SNV compendium underscores the importance of studying pathogenic variants in disease-relevant cells and implicates specific dysregulated gene networks in cancer predisposition. It also indicates that inherited cancer risk can impact the same gene via orthogonal genetic mechanisms of dysregulated expression as well as protein coding sequence alteration and demonstrates that a subset of germline-encoded risk genes also enable tumor growth of established cancers.
Project description:Single nucleotide variants (SNVs) in regulatory DNA are linked to inherited cancer risk. Massively parallel reporter assays (MPRA) of 5,031 SNVs linked to 14 neoplasms comprising >90% of human malignancies were performed in pertinent diploid cell types then integrated with matching chromatin accessibility, looping, and eQTL data to identify 411 regulatory SNVs and their putative target eGenes. The latter highlighted specific protein networks in lifetime cancer risk, including mitochondrial translation, proliferation, signaling, adhesion, and immunity. This cancer SNV compendium underscores the importance of studying pathogenic variants in disease-relevant cells and implicates specific dysregulated gene networks in cancer predisposition. It also indicates that inherited cancer risk can impact the same gene via orthogonal genetic mechanisms of dysregulated expression as well as protein coding sequence alteration and demonstrates that a subset of germline-encoded risk genes also enable tumor growth of established cancers.
Project description:We performed a targeted NGS using the commercial gene panel design ClearSeq Inherited Disease (Agilent Technologies) to identify the pathogenic sequence variants in two boys with neurodevelopmental disorders and epilepsy and their unaffected parents
Project description:We performed a targeted NGS using the commercial gene panel design ClearSeq Inherited Disease (Agilent Technologies) to identify the pathogenic sequence variants in children with ID/DD, ASD and MCA and their unaffected parents