12389 results for ""statistically+reactive"+taxa+in+microbial+community"

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• The Role of CTCF in the Organization of the Centromeric 11p15 Imprinted Domain Interactome

  Beckwith-Wiedemann Syndrome (BWS) is the most common human imprinting disorder and comprises a spectrum of overgrowth phenotypes. While approximately 35% of BWS cases are caused by isolated loss of methylation (LOM) at the human imprinting center 2 (IC2) on chromosome 11p15, only around 5% of patients develop BWS due to structural alterations to the IC2 domain. In this study, we identify a BWS-causing 7.6 kB familial deletion within the IC2 domain by performing Whole Genome Sequencing (WGS) on patient-derived human fibroblasts. Using a chromatin conformation capture technique, Capture C, on 3 control fibroblast samples, 3 BWS LOM fibroblast samples, and the single familial deletion sample, we investigate how the domain interactome changes in BWS patients. We find that high-strength interactions occur within the IC2 domain between the 5’ end of KCNQ1, KCNQ1 intron 2, and the 5’ end of CDKN1C in the control profile that are largely abrogated in the BWS samples, but some lower frequency contacts between the imprinting control region (ICR), KCNQ1 intron 2, and the 5’ end of CDKN1C are unaffected. We conclude that the strong KCNQ1-CDKN1C interactions are important in maintaining the domain imprint.

  Study phs002408

• TNF-induced dynamic regulation of mRNA stabilome in rheumatoid arthritis fibroblast-like synoviocytes

  During rheumatoid arthritis (RA), TNF activates fibroblast-like synoviocytes (FLS) inducing in a temporal order a constellation of genes, which perpetuate synovial inflammation. Although the molecular mechanisms regulating TNF-induced transcription are well characterized, little is known about the impact of mRNA stability on gene expression and the impact of TNF on decay rates of mRNA transcripts in FLS. To address these issues we performed RNA sequencing and genome-wide analysis of the mRNA stabilome in RA FLS. We found that TNF induces a biphasic gene expression program: initially, the inducible transcriptome consists primarily of unstable transcripts but progressively switches and becomes dominated by very stable transcripts. This temporal switch is due to: a) TNF-induced prolonged stabilization of previously unstable transcripts that enables progressive transcript accumulation over days and b) sustained expression and late induction of very stable transcripts. TNF- induced mRNA stabilization in RA FLS occurs during the late phase of TNF response, is MAPK-dependent, and involves several genes with pathogenic potential such as IL6, CXCL1, CXCL3, CXCL8/IL8, CCL2, and PTGS2. These results provide the first insights into genome-wide regulation of mRNA stability in RA FLS and highlight the potential contribution of dynamic regulation of the mRNA stabilome by TNF to chronic synovitis.

  Study phs001371

• Genome-Wide Assessment of DNA Methylation in Systemic Lupus Erythematosus-Related Autoantibodies

  Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can have debilitating effects on multiple organ systems. In SLE, the pivotal immunologic disturbance is the formation of autoantibodies directed against nuclear and cellular antigens. These autoantibodies are associated with specific organ manifestations. Our previous work has shown that certain single nucleotide polymorphisms (SNPs) are associated with the production of SLE-related autoantibodies. However, these genetic associations do not completely explain autoantibody development in SLE. Therefore, we examined whether epigenetic factors such as DNA methylation may be associated with the development of SLE-related autoantibodies. In this study, we examined whether differential DNA methylation is associated with anti-dsDNA, anti-SSA/Ro, anti-Smith, and anti-RNP autoantibodies. Using the Illumina HumanMethylation450 Beadchip, over 450,000 DNA methylation sites were characterized in 325 female SLE cases of European descent. Using a multivariable regression analyses, the methylation status of 16 CpG sites in 11 genes was found to be associated with the SLE-related autoantibodies under study. This study shows that epigenetic factors are associated with autoimmune disease phenotypes, and epigenetic studies are a complementary method to genetic association studies for understanding the biologic mechanisms contributing to autoimmune disease.

  Study phs000947

• Germline hypomorphic CARD11 mutations in severe atopic disease

  We described five patients from four unrelated families who had severe atopic dermatitis and susceptibility to mild skin viral infections. Some patients also exhibited other allergic symptoms such as asthma and food allergy. We performed targeted sequencing for affected patients A-I of family A and B-I of family B, whole exome sequencing for D-I, D-II.1 and healthy mother D-II.3 of family D, and whole genome sequencing for C-I and healthy mother C-II.2 of family C. We identified three different novel damaging missense mutations of CARD11 (GeneID:84433) in patients A-I (L194P), B-I (R975W), and C-I (E57D). In patients D-I and D-II.1, a dup183_196 (p.K196_V197insMKEERDSYNDELVK) mutation was found in the coil-coil domain of the protein. These mutations act as dominant negatives impeding the scaffolding function of the wild type protein, which leads to downstream NF-kB and mTORC1 signaling defects after TCR stimulation. Sanger sequencing later identified the corresponding CARD11 mutations in the affected family members (C-II.1, D-II.2) that are not included in the dbGaP submission. Hypomorphic CARD11 dominant negative mutants are novel causes of severe atopic disease.

  Study phs001369

• A Whole Genome Association Search for Type 2 Diabetes Genes in African Americans

  Over 2.8 million African Americans have type 2 diabetes mellitus (T2DM). This represents approximately 13% of the African American population and a significant proportion of the 21 million Americans living with diabetes. On average, an African American individual is twice as likely to have T2DM as a European American peer. Our research group has been actively involved in the study of African American diabetes genetics for over 15 years. We hypothesize that genes contributing to the development of T2DM in African Americans exist and can be located using modern molecular genetic methods. With the exception of TCF7L2(Transcription factor 7-like 2) evidence to date suggests variants that contribute T2DM risk in European-derived populations are not significant contributors to African American T2DM risk. We have performed a SNP-based Whole Genome Association (WGA) analysis on the Affymetrix 6.0 in a case control population of over 1000 African American T2DM cases and over 1000 non-diabetic controls. The DNAs have been collected from participants using uniform criteria from North Carolina and neighboring states. Genotype data will be subjected to extensive genetic analysis with the goal of defining a priority list of SNPs for genotyping in independent populations for confirmation and further detailed analysis.

  Study phs000140

• Rapid Evolution of a Skin Lightening Allele in Southern African KhoeSan

  The genetic architecture and polygenicity of skin pigmentation is explored in KhoeSan communities, including Nama individuals whose phenotype and genotype data are provided in this dataset. By pairing genotypes and quantitative spectrophotometric skin pigmentation phenotypes, we show that skin pigmentation is highly heritable in KhoeSan, yet known pigmentation loci only explains a small fraction of the phenotypic variance. Using genome-wide association analyses, we identified both canonical and non-canonical skin pigmentation loci. We show that this phenotype is more polygenic and complex than previously characterized. (Martin et al., Cell 2017. PMID: 29195075) Following up on the top associated signal with large effect size in the gene SLC24A5, we demonstrate that the canonical Eurasian nonsynonymous allele was introduced into KhoeSan via a recent migration ~2 kya and was under extremely strong selection. The derived allele was present at high frequency despite controlling for gene flow. With high-throughput sequences in the captured SLC24A5 region, we show that the most common derived haplotype is identical amongst Europeans, eastern African and KhoeSan. Using 4-population demographic simulations with selection, we show that the allele was introduced into the KhoeSan only 2,000 ya via a back-to-Africa migration and then experienced a selective sweep.

  Study phs001753

• Childhood Cancer Data Initiative (CCDI): Pediatric In Vivo Testing Program –Sarcoma, Kidney, and Liver Cancers

  The goal was to complete whole exome sequencing (WES) and RNA sequencing (RNA-Seq) on patient derived xenograft samples. Cancer in children is rare with approximately 15,700 new cases diagnosed annually in children 21 years or younger in the U.S. Through use of multimodality therapy (surgery, radiation therapy, and aggressive chemotherapy), 70% of patients will be 'cured' of their disease, and 5-year Event-Free Survival (EFS) exceeds 80%. Consequently, the number of patients that can be enrolled in phase I/II clinical trials is small, and most patients will have been extensively treated, hence drug/radiation resistant. Thus, preclinical studies that accurately translate into effective clinical therapy are an essential component of pediatric drug development. Our group has contributed to studies in the Pediatric Preclinical Testing Program (PPTP) and Pediatric Preclinical Testing Consortium (PPTC) that have led to clinical studies through Children's Oncology Group (COG). Of importance, we have developed and characterized over 330 Patient Derived Xenografts (PDX), developed from tumors both at diagnosis and relapse, that can be used to facilitate pediatric drug development as directed by FDA under the Research to Accelerate Cures and Equity for Children Act (RACE for Children Act).

  Study phs003160

• Drug Development against Tumor Microtube Networks in Glioblastoma

  Glioblastomas are aggressive brain tumors that resist current therapies by hijacking neurodevelopmental programs to invade the brain and form resilient multicellular networks. Tumor Microtubes (TMs), neurite-like processes extended by cancer cells, drive this pathobiology, but TM-inhibiting drugs are lacking. Here we developed a comprehensive, combined in vitro and in vivo drug screening approach, including novel AI-based analysis tools of TM parameters. Two Protein Kinase C (PKC) activators, TPPB and PMA, exhibited robust inhibition of TM formation in cell-based assays. Since unconnected glioblastoma cells exhibit increased sensitivity to cytotoxic therapy in vivo, brain tumor-bearing mice received TPPB, the most consistent TM-inhibiting compound, in combination with radiotherapy. Long-term intravital 2-photon microscopy confirmed anti-TM and anti-tumor effects of the co-treatment. Mechanistically, TPPB treatment inhibited several key molecular and functional components of TM-related glioblastoma cell network communication and decreased the expression of TTYH1, a key driver of invasive TMs. By establishing a novel screening pipeline for anti-TM drug development, our study identifies a druggable TM master regulator pathway and a small molecule with robust anti-TM effects. It provides a proof-of-principle that disrupting TMs and disconnecting tumor networks is a pharmacologically feasible strategy to make therapies against glioblastoma more effective.

  Study EGAS50000000477

• Rapid detection of expanded short tandem repeats in personal genomics using hybrid sequencing.

  Long expansions of short tandem repeats (STRs); i.e., DNA repeats of 2-6 nucleotides, are associated with some genetic diseases. Cost-efficient high throughput sequencing can quickly produce billions of short reads that would be useful for uncovering disease-associated STRs. However, enumerating STRs in short reads remains largely unexplored because of the difficulty in elucidating STRs much longer than 100 bp, the typical length of short reads. We propose ab initio procedures for sensing and locating long STRs promptly by utilizing the frequency distribution of all STRs and paired-end read information. We validated the reproducibility of this method using biological replicates and used it to locate an STR associated with a brain disease (SCA31). Subsequently, we sequenced this STR site in eleven SCA31 samples using SMRT? sequencing (Pacific Biosciences), determined 2.3-3.1 kb sequences at nucleotide resolution, and revealed that (TGGAA)- and (TAAAATAGAA)-repeat expansions determined the instability of the repeat expansions associated with SCA31. Our method could also identify common STRs, (AAAG)- and (AAAAG)-repeat expansions, which are remarkably expanded at four positions in an SCA31 sample. This is the first proposed method for rapidly finding disease-associated long STRs in personal genomes using hybrid sequencing of short and long reads.

  Study JGAS000002

• Finding the way towards the eradication of therapy-related myeloid neoplasms

  Therapy-related neoplasms are directly caused by the drugs used to eradicate a previous cancer. It is well known that a subset of drugs designed to kill cancer cells through DNA-damage-induced apoptosis can intrinsically, as secondary effect, cause DNA-damage in other cells, thus inducing a neoplasm. Those neoplasms have especially bad prognosis. Why are these drugs still in use? Because for many diseases we do not have anything better, at the moment. Approximately 0.5-1% of the kids treated for various types of cancers develop a therapy-related myeloid neoplasm (tMN) as a result of the treatment. Despite having the same origin, their prognostic and molecular features are different from the adult ones, and a complete understanding of the pathogenesis of tMN in children is still missing. A total of 84 paediatrics neoplasms have been profiled by either Whole Genome or Whole Exome sequencing by Jason R. Schwartz and his colleagues, in a collaborative effort guided at the St. Jude Children's hospital, in Memphis. They identified a mean of 28 somatic mutations per patient, a number which is significantly bigger than the number of mutations found in paediatrics primary neoplasms, as depicted in the original paper's figure 1b, shown here. Their sequencing data identified that Ras/MAPK pathway mutations, alterations in RUNX1 or TP53, and KMT2A rearrangements as the most frequent drivers of the disease. Clonal evolution analysis (the comparative study of the behaviour of cells harbouring different mutations) highlighted that, unlike in adults’ tMN, there were not pre-existing leukemic clones, and virtually all mutated cells were found arising as a direct consequence of cytotoxic therapy. This represents yet another important difference between adult and paediatric tMN. This important study have been published in Nature communications in February 2021. The sequencing data have been deposited at EGA under the study number EGAS00001004850. Thanks to this, other researchers around the world could re-use it to uncover more information, integrate and validate their studies. Revealing the molecular features underlying the development of cancers is the only way towards the development of new generation targeted therapies, which will allow us to finally drop the cytotoxic drugs eliciting such unwanted and catastrophic secondary effects as tMN. It is not an overstatement to say that, while improving the treatment of primary tumours, we could entirely eradicate therapy-related neoplasms right from their origin. Looking forward.

  Blog eradication-of-therapy-related-myeloid-neoplasms