20 research outputs found
Regulation of gene expression in human brain using transcriptome sequencing
Characterising the molecular mechanisms underlying disease risk variants identified in genome-wide association studies (GWAS) is of major interest. Expression Quantitative Trait Loci (eQTL) mapping studies provide a genome-wide characterisation of the impact of common genetic variation on gene expression and splicing and therefore have the potential to achieve this. In this thesis, I investigated the effect of common genetic variants in human brain through eQTL analysis. As part of the UK Brain Expression Consortium project, the analyses in this PhD thesis were performed on whole transcriptome RNA sequencing data from neuropathologically normal human post-mortem brain. I conducted eQTL analyses on putamen and substantia nigra using different types of quantification in order to interrogate regulation at different stages of RNA processing. This analysis pointed to splicing as an important process for the pathogenesis of Parkison’s Disease. Thus, I identify not only disease-relevant regulatory loci but also the types of analyses yielding the most disease-specific information. Due to the limitations of current gene annotation and the complex transcriptomic landscape in human brain, I investigated transcription and splicing in the hippocampus using annotation-agnostic methods. This not only revealed the existence of widespread gene misannotation in the human brain, but also revealed the limitation of current quantification methods to capture transcriptome complexity in brain. Therefore, a reference-free eQTL analysis was performed and by testing for eQTL-GWAS co-localisation I found that incomplete annotation of the brain transcriptome limits the interpretation of risk loci for neurological disorders. I anticipate that analyses of this kind will have an increasing impact on our understanding of a range of disorders, but are likely to have most impact on neurological and neuropsychiatric disorders because of the high transcriptome complexity of human brain tissue
Regulatory sites for splicing in human basal ganglia are enriched for disease-relevant information
Genome-wide association studies have generated an increasing number of common genetic variants associated with neurological and psychiatric disease risk. An improved understanding of the genetic control of gene expression in human brain is vital considering this is the likely modus operandum for many causal variants. However, human brain sampling complexities limit the explanatory power of brain-related expression quantitative trait loci (eQTL) and allele-specific expression (ASE) signals. We address this, using paired genomic and transcriptomic data from putamen and substantia nigra from 117 human brains, interrogating regulation at different RNA processing stages and uncovering novel transcripts. We identify disease-relevant regulatory loci, find that splicing eQTLs are enriched for regulatory information of neuron-specific genes, that ASEs provide cell-specific regulatory information with evidence for cellular specificity, and that incomplete annotation of the brain transcriptome limits interpretation of risk loci for neuropsychiatric disease. This resource of regulatory data is accessible through our web server, http://braineacv2.inf.um.es/
Identification of novel risk loci, causal insights, and heritable risk for Parkinson's disease: a meta-analysis of genome-wide association studies
Background Genome-wide association studies (GWAS) in Parkinson's disease have increased the scope of biological knowledge about the disease over the past decade. We aimed to use the largest aggregate of GWAS data to identify novel risk loci and gain further insight into the causes of Parkinson's disease. Methods We did a meta-analysis of 17 datasets from Parkinson's disease GWAS available from European ancestry samples to nominate novel loci for disease risk. These datasets incorporated all available data. We then used these data to estimate heritable risk and develop predictive models of this heritability. We also used large gene expression and methylation resources to examine possible functional consequences as well as tissue, cell type, and biological pathway enrichments for the identified risk factors. Additionally, we examined shared genetic risk between Parkinson's disease and other phenotypes of interest via genetic correlations followed by Mendelian randomisation. Findings Between Oct 1, 2017, and Aug 9, 2018, we analysed 7·8 million single nucleotide polymorphisms in 37 688 cases, 18 618 UK Biobank proxy-cases (ie, individuals who do not have Parkinson's disease but have a first degree relative that does), and 1·4 million controls. We identified 90 independent genome-wide significant risk signals across 78 genomic regions, including 38 novel independent risk signals in 37 loci. These 90 variants explained 16–36% of the heritable risk of Parkinson's disease depending on prevalence. Integrating methylation and expression data within a Mendelian randomisation framework identified putatively associated genes at 70 risk signals underlying GWAS loci for follow-up functional studies. Tissue-specific expression enrichment analyses suggested Parkinson's disease loci were heavily brain-enriched, with specific neuronal cell types being implicated from single cell data. We found significant genetic correlations with brain volumes (false discovery rate-adjusted p=0·0035 for intracranial volume, p=0·024 for putamen volume), smoking status (p=0·024), and educational attainment (p=0·038). Mendelian randomisation between cognitive performance and Parkinson's disease risk showed a robust association (p=8·00 × 10−7). Interpretation These data provide the most comprehensive survey of genetic risk within Parkinson's disease to date, to the best of our knowledge, by revealing many additional Parkinson's disease risk loci, providing a biological context for these risk factors, and showing that a considerable genetic component of this disease remains unidentified. These associations derived from European ancestry datasets will need to be followed-up with more diverse data. Funding The National Institute on Aging at the National Institutes of Health (USA), The Michael J Fox Foundation, and The Parkinson's Foundation (see appendix for full list of funding sources)
Novel genetic loci associated with hippocampal volume
The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg =-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness
Novel genetic loci underlying human intracranial volume identified through genome-wide association
Intracranial volume reflects the maximally attained brain size during development, and remains stable with loss of tissue in late life. It is highly heritable, but the underlying genes remain largely undetermined. In a genome-wide association study of 32,438 adults, we discovered five novel loci for intracranial volume and confirmed two known signals. Four of the loci are also associated with adult human stature, but these remained associated with intracranial volume after adjusting for height. We found a high genetic correlation with child head circumference (ρgenetic=0.748), which indicated a similar genetic background and allowed for the identification of four additional loci through meta-analysis (Ncombined = 37,345). Variants for intracranial volume were also related to childhood and adult cognitive function, Parkinson’s disease, and enriched near genes involved in growth pathways including PI3K–AKT signaling. These findings identify biological underpinnings of intracranial volume and provide genetic support for theories on brain reserve and brain overgrowth
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Identification of candidate Parkinson disease genes by integrating genome-wide association study, expression, and epigenetic data sets
Importance Substantial genome-wide association study (GWAS) work in Parkinson disease (PD) has led to the discovery of an increasing number of loci shown reliably to be associated with increased risk of disease. Improved understanding of the underlying genes and mechanisms at these loci will be key to understanding the pathogenesis of PD.
Objective To investigate what genes and genomic processes underlie the risk of sporadic PD.
Design and Setting This genetic association study used the bioinformatic tools Coloc and transcriptome-wide association study (TWAS) to integrate PD case-control GWAS data published in 2017 with expression data (from Braineac, the Genotype-Tissue Expression [GTEx], and CommonMind) and methylation data (derived from UK Parkinson brain samples) to uncover putative gene expression and splicing mechanisms associated with PD GWAS signals. Candidate genes were further characterized using cell-type specificity, weighted gene coexpression networks, and weighted protein-protein interaction networks.
Main Outcomes and Measures It was hypothesized a priori that some genes underlying PD loci would alter PD risk through changes to expression, splicing, or methylation. Candidate genes are presented whose change in expression, splicing, or methylation are associated with risk of PD as well as the functional pathways and cell types in which these genes have an important role.
Results Gene-level analysis of expression revealed 5 genes (WDR6 [OMIM 606031], CD38 [OMIM 107270], GPNMB [OMIM 604368], RAB29 [OMIM 603949], and TMEM163 [OMIM 618978]) that replicated using both Coloc and TWAS analyses in both the GTEx and Braineac expression data sets. A further 6 genes (ZRANB3 [OMIM 615655], PCGF3 [OMIM 617543], NEK1 [OMIM 604588], NUPL2 [NCBI 11097], GALC [OMIM 606890], and CTSB [OMIM 116810]) showed evidence of disease-associated splicing effects. Cell-type specificity analysis revealed that gene expression was overall more prevalent in glial cell types compared with neurons. The weighted gene coexpression performed on the GTEx data set showed that NUPL2 is a key gene in 3 modules implicated in catabolic processes associated with protein ubiquitination and in the ubiquitin-dependent protein catabolic process in the nucleus accumbens, caudate, and putamen. TMEM163 and ZRANB3 were both important in modules in the frontal cortex and caudate, respectively, indicating regulation of signaling and cell communication. Protein interactor analysis and simulations using random networks demonstrated that the candidate genes interact significantly more with known mendelian PD and parkinsonism proteins than would be expected by chance.
Conclusions and Relevance Together, these results suggest that several candidate genes and pathways are associated with the findings observed in PD GWAS studies
<i>SCFD1</i> expression quantitative trait loci in amyotrophic lateral sclerosis are differentially expressed
Abstract
Evidence indicates that common variants found in genome-wide association studies increase risk of disease through gene regulation via expression Quantitative Trait Loci. Using multiple genome-wide methods, we examined if Single Nucleotide Polymorphisms increase risk of Amyotrophic Lateral Sclerosis through expression Quantitative Trait Loci, and whether expression Quantitative Trait Loci expression is consistent across people who had Amyotrophic Lateral Sclerosis and those who did not. In combining public expression Quantitative Trait Loci data with Amyotrophic Lateral Sclerosis genome-wide association studies, we used Summary-data-based Mendelian Randomization to confirm that SCFD1 was the only gene that was genome-wide significant in mediating Amyotrophic Lateral Sclerosis risk via expression Quantitative Trait Loci (Summary-data-based Mendelian Randomization beta = 0.20, standard error = 0.04, P-value = 4.29 × 10−6). Using post-mortem motor cortex, we tested whether expression Quantitative Trait Loci showed significant differences in expression between Amyotrophic Lateral Sclerosis (n = 76) and controls (n = 25), genome-wide. Of 20 757 genes analysed, the two most significant expression Quantitative Trait Loci to show differential in expression between Amyotrophic Lateral Sclerosis and controls involve two known Amyotrophic Lateral Sclerosis genes (SCFD1 and VCP). Cis-acting SCFD1 expression Quantitative Trait Loci downstream of the gene showed significant differences in expression between Amyotrophic Lateral Sclerosis and controls (top expression Quantitative Trait Loci beta = 0.34, standard error = 0.063, P-value = 4.54 × 10−7). These SCFD1 expression Quantitative Trait Loci also significantly modified Amyotrophic Lateral Sclerosis survival (number of samples = 4265, hazard ratio = 1.11, 95% confidence interval = 1.05–1.17, P-value = 2.06 × 10−4) and act as an Amyotrophic Lateral Sclerosis trans-expression Quantitative Trait Loci hotspot for a wider network of genes enriched for SCFD1 function and Amyotrophic Lateral Sclerosis pathways. Using gene-set analyses, we found the genes that correlate with this trans-expression Quantitative Trait Loci hotspot significantly increase risk of Amyotrophic Lateral Sclerosis (beta = 0.247, standard deviation = 0.017, P = 0.001) and schizophrenia (beta = 0.263, standard deviation = 0.008, P-value = 1.18 × 10−5), a disease that genetically correlates with Amyotrophic Lateral Sclerosis. In summary, SCFD1 expression Quantitative Trait Loci are a major factor in Amyotrophic Lateral Sclerosis, not only influencing disease risk but are differentially expressed in post-mortem Amyotrophic Lateral Sclerosis. SCFD1 expression Quantitative Trait Loci show distinct expression profiles in Amyotrophic Lateral Sclerosis that correlate with a wider network of genes that also confer risk of the disease and modify the disease’s duration.</jats:p
PALVELUTUOTTEEN HINNOITTELUN KEHITTÄMINEN
Tämän opinnäytetyön aiheena on palvelutuotteen hinnoittelun kehittäminen. Tutkimuksen kohteena on Tili- ja isännöitsijätoimisto Ky. Tili- ja isännöitsijätoimisto Ky on Vaasassa toimiva tili- ja isännöintitoimisto, joka tarjoaa taloushallinto- ja isännöintipalveluita yrityksille. Tutkimuksen tavoitteena on kehittää Tili- ja isännöitsijätoimisto Ky:n isännöitsijän palvelutuotteiden hinnoittelua.
Hinnoittelumenetelmäksi valittiin toimintoperusteinen hinnoittelu, jonka lähtökohtana on selvittää asiakaskohtaisia välillisiä kustannuksia. Kysymys oli suorite-kohtaisten kustannusten laskemisesta, eli toimintoperusteisesta prosessilaskennasta. Toimintoperusteinen prosessilaskenta tukee hinnoittelun päätöstä. Toiminto-analyysin jälkeen selvitettiin resurssien kohdistumista yrityksen eri toiminnoille.
Aluksi selvitettiin yrityksen kustannusajuri, jonka perusteella kustannukset on kohdistettu eri toiminnoille. Seuraavaksi selvitettiin toimintoajurin avulla toimintoihin liittyvät yksikkökustannukset. Tuotteiden hinnoittelussa myyntihinnan on tarkoituksena sisältää kaikkien kustannusten lisäksi voittotavoite.
Tutkimuksen teoriaosuuden keskeisiä asioita ovat toimintoperusteisen kustannuslaskennan, sekä hinnoittelun perusteiden esittely. Niiden avulla voidaan perustella hinnoittelupäätöstä tukeva toimintolaskenta. Opinnäytetyössä esitellään lisäksi kustannusperusteista hinnoittelua sekä isännöintiä ja tilitoimistoa yleisesti.
Tutkimusmenetelmänä käytettiin kvalitatiivista eli laadullista tutkimusta. Tutkimuksen teoriaosuuteen käytettiin toimintolaskennan, taloushallinnon alan sekä hinnoittelun teoriaan liittyvää kirjallisuutta. Aineistonkeruussa havainnoitiin yrityksen tilinpäätöstä vuodelta 2016 ja yrityksen toimintaa liittyviä ohjelmia sekä tietokantoja. Lisäksi haastateltiin Tili- ja isännöitsijätoimisto Ky:n omistajaa ja työntekijöitä.This research was designed to develop the used pricing method for the case firm Tili- ja isännöitsijätoimisto Ky. The main area of this research focused on the main service products in property management. The case firm offers financial accounting and management services to house companies and other customer companies.
Activity based costing was selected as the new pricing method in order to identify the customer-specific indirect costs. The aim of activity-based costing was to support pricing decisions for the case firm. In the implementation steps, activities must be identified first, and then the process continues with an activity analysis. Once the costs of activity and its drivers have been identified and its costs have been determined, then the costs of activity is allocated to the service product. In the allocation process, when the activity driver has been determined, the cost per unit can then be determined. Once the product cost per unit has been determined then the case firm considers the generated value of its service product, so the pricing of all the service product sales cover the fixed expenses with any remaining contribution margin providing profits.
The theoretical study of this thesis introduced activity based costing and pricing to support activity based cost implementation and pricing decisions. In addition, it introduced cost based pricing and property management business and accounting firms in general.
This research was implemented using the qualitative research method. The research material consists of related activity based costing, financial management, management accounting and pricing literature. The theoretical information was gathered from scientific research, academic books and some material was collect-ed from the Internet. The empirical data in this research was gathered by observing the case company’s financial statement from the year 2016 together with some business activities related programs and databases. In addition, was collected by interviewing the case company owner and the other employers of the company
Identification of sixteen novel candidate genes for late onset Parkinson's disease
Altres ajuts: Italian Ministry of Health grant (RF 2019-12370224, GR2016-02362247); Italian Ministry of Economic Development (F/0009/00X26); Fondazione Umberto Veronesi.Background: Parkinson's disease (PD) is a neurodegenerative movement disorder affecting 1-5% of the general population for which neither effective cure nor early diagnostic tools are available that could tackle the pathology in the early phase. Here we report a multi-stage procedure to identify candidate genes likely involved in the etiopathogenesis of PD. Methods: The study includes a discovery stage based on the analysis of whole exome data from 26 dominant late onset PD families, a validation analysis performed on 1542 independent PD patients and 706 controls from different cohorts and the assessment of polygenic variants load in the Italian cohort (394 unrelated patients and 203 controls). Results: Family-based approach identified 28 disrupting variants in 26 candidate genes for PD including PARK2, PINK1, DJ-1(PARK7), LRRK2, HTRA2, FBXO7, EIF4G1, DNAJC6, DNAJC13, SNCAIP, AIMP2, CHMP1A, GIPC1, HMOX2, HSPA8, IMMT, KIF21B, KIF24, MAN2C1, RHOT2, SLC25A39, SPTBN1, TMEM175, TOMM22, TVP23A and ZSCAN21. Sixteen of them have not been associated to PD before, were expressed in mesencephalon and were involved in pathways potentially deregulated in PD. Mutation analysis in independent cohorts disclosed a significant excess of highly deleterious variants in cases (p = 0.0001), supporting their role in PD. Moreover, we demonstrated that the co-inheritance of multiple rare variants (≥ 2) in the 26 genes may predict PD occurrence in about 20% of patients, both familial and sporadic cases, with high specificity (> 93%; p = 4.4 × 10). Moreover, our data highlight the fact that the genetic landmarks of late onset PD does not systematically differ between sporadic and familial forms, especially in the case of small nuclear families and underline the importance of rare variants in the genetics of sporadic PD. Furthermore, patients carrying multiple rare variants showed higher risk of manifesting dyskinesia induced by levodopa treatment. Conclusions: Besides confirming the extreme genetic heterogeneity of PD, these data provide novel insights into the genetic of the disease and may be relevant for its prediction, diagnosis and treatment