Project description:TrEMOLO : Accurate transposable element allele frequency estimation using long-read sequencing data combining assembly and mapping-based approaches
| PRJEB54012 | ENA
Project description:Molecular inversion probe based sequencing of Peruvian Plasmodium vivax
Project description:Climate change is impacting human health through a historic rise in wildfire smoke across the United States and the world. Whereas the deleterious effects of wildfire smoke and associated air pollution on asthma outcomes are well-established epidemiologically, genetic risks and molecular mechanisms of how wildfire smoke affects asthma are unknown. This knowledge gap hinders the identification of high-risk individuals and the creation of targeted therapies or recommendations to protect these individuals. Here, we employ a genetic approach to identify common variant (minor allele frequency > 0.05) exposure-conditional genetic risk variants that localize with genomic responses to wood smoke particles (WSP), a model of wildfire smoke exposure, and associate with asthma in the Genetic Epidemiology Research on Aging (GERA) cohort. Our novel approach used nascent transcriptional signatures derived from WSP-exposed Beas-2B airway epithelial cells to reduce the genome sequence for discovery and allow a permutation-based statistical approach to identify 52 candidate SNPs. We applied biologic and bioinformatic filters to prioritize variants for direct testing of allele-dependent transcriptional regulatory function in plasmid reporters. The rs3861144 variant identified by this approach controls WSP responses of airway epithelial cells to SPRY2, which we showed is involved in mechanical injury repair in cell culture. Our results demonstrate that wildfire particulates contribute to asthma risk at the molecular level, and we have identified mechanistic targets and genetic variant candidates to apply for clinical risk prediction and development of targeted therapies for high-risk individuals.
Project description:PIK3CA-related overgrowth syndromes (PROS) are caused by somatic variants that result in constitutive activation of the phosphatidylinositol-3-kinase/AKT/mTOR pathway. Promising responses to molecularly targeted therapy have been reported, however identification of an appropriate agent can be hampered by the mosaic nature and low variant allele frequency of the causal variant. Moreover, our understanding of the molecular repercussions of these variants at the single cell level remain limited. Here we report in vitro expansion of affected tissue followed by exome sequencing and combined 3’ whole transcriptome and targeted long-read single cell RNA-sequencing in a patient with clinical symptoms consistent with Megalencephaly-Capillary Malformation Syndrome (MCAP, a PROS condition). This approach identified a targetable PIK3CA variant restricted to a PAX3+ fibroblast population. These studies highlight the utility of novel next-generation sequencing strategies in the management of suspected syndromes of somatic mosaicism and provide insight into the underlying pathophysiology of a debilitating genetic syndrome.
Project description:Identifying genes where a variant allele is preferentially expressed in tumors could lead to a better understanding of cancer biology and optimization of targeted therapy. However, tumor sample heterogeneity complicates standard approaches for detecting preferential allele expression. We therefore developed a novel approach combining genome and transcriptome sequencing data from the same sample that corrects for sample heterogeneity and identifies significant preferentially expressed alleles. We applied this analysis to epithelial ovarian cancer samples consisting of matched primary ovary and peritoneum and lymph node metastasis. We find that preferentially expressed variant alleles include germline and somatic variants, are shared at a relatively high frequency between patients and are in gene networks known to be involved in cancer processes. Analysis at a patient level identifies patient-specific preferentially expressed alleles in genes that are targets for known drugs. Analysis at a site level identifies patterns of site specific preferential allele expression with similar pathways being impacted in the primary and metastasis sites. We conclude that genes with preferentially expressed variant alleles can act as cancer drivers and that targeting those alleles could lead to new therapeutic strategies. Three cancer patients, three tumor samples per patient from different sites, two normal tissue samples from two different patients, four cell lines.
Project description:Genetic Diagnosis of Rubinstein-Taybi Syndrome with Multiplex Ligation-dependent Probe Amplification (MLPA) and Whole Exome Sequencing (WES): Case Series with a Novel CREBBP Variant
Project description:Identifying genes where a variant allele is preferentially expressed in tumors could lead to a better understanding of cancer biology and optimization of targeted therapy. However, tumor sample heterogeneity complicates standard approaches for detecting preferential allele expression. We therefore developed a novel approach combining genome and transcriptome sequencing data from the same sample that corrects for sample heterogeneity and identifies significant preferentially expressed alleles. We applied this analysis to epithelial ovarian cancer samples consisting of matched primary ovary and peritoneum and lymph node metastasis. We find that preferentially expressed variant alleles include germline and somatic variants, are shared at a relatively high frequency between patients and are in gene networks known to be involved in cancer processes. Analysis at a patient level identifies patient-specific preferentially expressed alleles in genes that are targets for known drugs. Analysis at a site level identifies patterns of site specific preferential allele expression with similar pathways being impacted in the primary and metastasis sites. We conclude that genes with preferentially expressed variant alleles can act as cancer drivers and that targeting those alleles could lead to new therapeutic strategies.
Project description:Genome-directed oncology has the potential to revolutionize patient treatment, but is limited by an abundance of rare, uncharacterized and therapeutically uninformative somatic variants. To accelerate characterization of the “long tail” of rare somatic variants, we quantified the activity and drug responsiveness of virtually all possible (99.84%) missense variants in the Ser/Thr kinase MAPK1/ERK2. We identified recurrent and rare hypermorphic and loss-of-function alleles, revealing that variant activity is uncorrelated with mutational frequency. Somatic ERK2 variants displayed variable responses to RAF-, MEK- and ERK-directed therapies, potentially informing clinical treatment strategies for patients whose tumors harbor these alterations. A subset of recurrent and rare somatic variants co-localized on ERK2 protein-protein interfaces, yet engendered contrasting phenotypes based on their specific sub-domain localization. The approach presented here represents an allele-characterization framework that compliments existing computational efforts and supports current and future somatic variant discovery efforts, advancing the promise of genome-guided treatment strategies.