Label-free and redox proteomic analyses of the triacylglycerol-accumulating Rhodococcus jostii RHA1

The bacterium Rhodococcus jostii RHA1 synthesizes large amounts of triacylglycerols (TAG) under conditions of nitrogen starvation. To better understand the molecular mechanisms behind this process, we performed proteomic studies in this oleaginous bacterium. Upon nitrogen starvation, we observed a re-routing of the carbon flux towards the formation of TAG. Under these conditions, the cellular lipid content made up more than half of the cell?s dry weight. On the proteome level, this coincided with a shift towards non-glycolytic carbohydrate-metabolizing pathways. These pathways (Entner-Doudoroff and pentose-phosphate shunt) contribute NADPH and precursors of glycerol-3-phosphate and acetyl-CoA to lipogenesis. The expression of proteins involved in the degradation of branched-chain-amino acids and the methyl malonyl-CoA pathway probably provided propionyl-CoA for the biosynthesis of odd-numbered fatty acids, which make up almost 30% of RHA1 fatty acid composition. Additionally, lipolytic and glycerol-degrading enzymes increased in abundance, suggesting a dynamic cycling of cellular lipids. Conversely, abundance of proteins involved in consuming intermediates of lipogenesis decreased. Furthermore, we identified another level of lipogenesis regulation through redox-mediated thiol modification in R. jostii. Enzymes affected included acetyl-CoA carboxylase and a β-ketoacyl-[ACP] synthase II (FabF). An integrative metabolic model for the oleaginous RHA1 strain is proposed based on our results.Fil: Dávila Costa, José Sebastián. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Herrero, O. Marisa. Universidad Nacional de la Patagonia "san Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro; ArgentinaFil: Alvarez, Hector Manuel. Universidad Nacional de la Patagonia "san Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Leichert, Lars. Ruhr-Universitat Bochum; Alemani

Insights into the metabolism of oleaginous Rhodococcus spp

Some species belonging to the Rhodococcus genus, such as Rhodococcus opacus, R. jostii, and R. wratislaviensis, are known to be oleaginous microorganisms, since they are able to accumulate triacylglycerols (TAG) at more than 20% of their weight (dry weight). Oleaginous rhodococci are promising microbial cell factories for the production of lipids to be used as fuels and chemicals. Cells could be engineered to create strains capable of producing high quantities of oils from industrial wastes and a variety of high-value lipids. The comprehensive understanding of carbon metabolism and its regulation will contribute to the design of a reliable process for bacterial oil production. Bacterial oleagenicity requires an integral configuration of metabolism and regulatory processes rather than the sole existence of an efficient lipid biosynthesis pathway. In recent years, several studies have been focused on basic aspects of TAG biosynthesis and accumulation using R. opacus PD630 and R. jostii RHA1 strains as models of oleaginous bacteria. The combination of results obtained in these studies allows us to propose a metabolic landscape for oleaginous rhodococci. In this context, this article provides a comprehensive and integrative view of different metabolic and regulatory attributes and innovations that explain the extraordinary ability of these bacteria to synthesize and accumulate TAG. We hope that the accessibility to such information in an integrated way will help researchers to rationally select new targets for further studies in the field.Fil: Alvarez, Héctor M.. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; ArgentinaFil: Herrero, O. Marisa. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; ArgentinaFil: Silva, Roxana A.. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; ArgentinaFil: Hernández, Martín A.. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; ArgentinaFil: Lanfranconi, Mariana Patricia. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; ArgentinaFil: Villalba, María Soledad. Universidad Nacional de la Patagonia "San Juan Bosco". Instituto de Biociencias de la Patagonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biociencias de la Patagonia; Argentin

Physiological and genetic differences amongst Rhodococcus species for using glycerol as a source for growth and triacylglycerol production

We analysed the ability of five different rhodococcal species to grow and produce triacylglycerols (TAGs) from glycerol, the main byproduct of biodiesel production. Rhodococcus fascians and Rhodococcus erythropolis grew fast on glycerol, whereas Rhodococcus opacus and Rhodococcus jostii exhibited a prolonged lag phase of several days before growing. Rhodococcus equi only exhibited poor growth on glycerol. R. erythropolis DSMZ 43060 and R. fascians F7 produced 3.9–4.3 g cell biomass l and 28.4–44.6% cellular dry weight (CDW) of TAGs after 6 days of incubation; whereas R. opacus PD630 and R. jostii RHA1 produced 2.5–3.8 g cell biomass l and 28.3–38.4% CDW of TAGs after 17 days of growth on glycerol. Genomic analyses revealed two different sets of genes for glycerol uptake and degradation (here named clusters 1 and 2) amongst rhodococci. Those species that possessed cluster 1 (glpFK1D1) (R. fascians and R. erythropolis) exhibited fast growth and lipid accumulation, whereas those that possessed cluster 2 (glpK2D2) (R. opacus, R. jostii and R. equi) exhibited delayed growth and lipid accumulation during cultivation on glycerol. Three glycerol-negative strains were complemented for their ability to grow and produce TAGs by heterologous expression of glpK2 from R. opacus PD630. In addition, we significantly reduced the extension of the lag phase and improved glycerol assimilation and oil production of R. opacus PD630 when expressing glpK1D1 from R. fascians. The results demonstrated that rhodococci are a flexible and amenable biological system for further biotechnological applications based on the reutilization of glycerol.This study was financially supported by the SCyT of the University of Patagonia San Juan Bosco, the Agencia Comodoro Conocimiento (MCR), Oil m&s Company, CONICET (project PIP-CONICET 0764), COFECyT (project PFIP CHU-25) and ANPCyT (project PICT2012 2031), Argentina. H. M. A. is a career investigator of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.Peer Reviewe

Risk of adverse outcomes in offspring with RT-PCR confirmed prenatal Zika virus exposure: an individual participant data meta-analysis of 13 cohorts in the Zika Brazilian Cohorts

The Zika Brazilian Cohorts Consortium was supported by the National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq) (grant number 404861/2018-0). The individual studies participating in the ZBC-Consortium were funded by: Wellcome Trust and the United Kingdom’s Department for International Development (grant numbers: 205377/Z/16/Z; 201870/Z/16/Z). European Union’s Horizon 2020 research and innovation programme under ZikaPLAN (grant number 734584). Wellcome Trust - Research Enrichment in Epidemic Situation (grant number 107779/Z/15/Z; with ER1505 & ER1601). Medical Research Council on behalf of the Newton Fund and Wellcome Trust (grant number MC_PC_15088). National Institutes of Health/National Institute of Allergy and Infectious Diseases (grant number RO1/ AI140718). Fondation Christophe et Rodolphe Mérieux. National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq) (grant numbers 443875/2018-9; 440573/2016-5; 441098/2016-9; 305090/2016-0; 307282/2017-1; 304476/2018-8; 465549/2014-4; 440763/2016-9; 309722/2017-9; 306708/2014-0; 440577/2016-0). Coordination for the improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Capes) (grant numbers 88881.130813/2016-01; 88887.116627/2016-01; 88887.136366/2017-00). Ministry of Health of Brazil - Emergency Response in Public Health - Zika virus and Microcephaly (Ministério da Saúde de Brasil - Resposta à Emergência em Saúde Pública – Zika vírus e Microcefalia) (grant number 837058/2016). Department of Science and Technology (Departamento de Ciência e Tecnologia - DECIT) (grant numbers 25000.072811/2016-19; 440839/2016-5). Foundation of Research Support of the State of São Paulo (Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP) (grant numbers 2016/08578-0; 2017/21688-1; 2013/21719-3; 2016/ 15021-1; 2015/12295-0; 2016/05115-9). Foundation of Research Support of the State of Rio de Janeiro (Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro – FAPERJ) (grant numbers E-26/201.351/2016; E-18/ 2015TXB; E-26/202.862/2018; E 26/010.002477/2016). Foundation of Support for Research and Scientific and Technological Development of Maranhão (Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão – FAPEMA) (grant number 008/2016). Brazilian Ministry of Health (Ministério da Saúde – MS) (grant number 929698560001160-02). Evandro Chagas Institute/Brazilian Ministry of Health (Instituto Evandro Chagas/Ministério da Saúde). Foundation of Research Support of the State of Goiás (Fundação de Amparo à Pesquisa do Estado de Goiás – FAPEG) (number grant 2017/10267000531). Foundation of Research Support of the State of Rio Grande do Sul (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul – FAPERGS) (grant number 17/2551-0000521-0). Foundation to Support Teaching, Research and Assistance at Hospital das Clínicas, Faculty of Medicine of Ribeirão Preto (Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto) and São Paulo State Department of Health (Secretaria de Saúde do Estado de São Paulo). Support Foundation of Pernambuco Science and Technology (Fundação de Amparo à Ciência e Tecnologia de Pernambuco – FACEPE) (grant numbers APQ-0172-4.01/16; APQ-0192-4.01/17; APQ0793-4.01/17).Federal University of Pernambuco. Postgraduate Program in Tropical Medicine. Recife, PE, Brazil / University of Pernambuco. Post-Graduation in Health Sciences. Recife, PE, Brazil.University of Pernambuco. Post-Graduation in Health Sciences. Recife, PE, Brazil.London School of Hygiene & Tropical Medicine. Department of Infectious Disease Epidemiology. London, UK.Federal University of Pernambuco. Postgraduate Program in Collective Health. Recife, PE, Brazil.University of Pernambuco. Post-Graduation in Health Sciences. Recife, PE, Brazil.University of Amazonas State. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil / Doctor Heitor Vieira Dourado Tropical Medicine Foundation. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil.Ribeirão Preto Medical School. Department of Pediatrics. Ribeirão Preto, SP, Brazil.Ribeirão Preto Medical School. Department of Gynecology and Obstetrics. Ribeirão Preto, SP, Brazil.Ribeirão Preto Medical School. Department of Gynecology and Obstetrics. Ribeirão Preto, SP, Brazil.Ribeirão Preto Medical School. Department of Pediatrics. Ribeirão Preto, SP, Brazil.University of Amazonas State. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil / Doctor Heitor Vieira Dourado Tropical Medicine Foundation. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil.University of Amazonas State. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil / Doctor Heitor Vieira Dourado Tropical Medicine Foundation. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil.Instituto Fernandes Figueira. Clinical Research Unit. Rio de Janeiro, RJ, Brazil.Oswaldo Cruz Foundation. Instituto Fernandes Figueira. Clinical Research Unit. Rio de Janeiro, RJ, Brazil.Oswaldo Cruz Foundation. Instituto Fernandes Figueira. Obstretics. Rio de Janeiro, RJ, Brazil.University of California. David Geffen School of Medicine. Department of Pediatrics. Los Angeles, CA, Estados Unidos.Oswaldo Cruz Foundation. Research Center Aggeu Magalhães. Recife, PE, Brazil.London School of Hygiene & Tropical Medicine. Department of Infectious Disease Epidemiology. London, UK.Oswaldo Cruz Foundation. Research Center Aggeu Magalhães. Recife, PE, Brazil.Altino Ventura Foundation. Department of Ophthalmology. Recife, PE, Brazil / Pernambuco Eyes Hospital. Recife, PE, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Medicine School of São José do Rio Preto. Department of Infectious Disease. São José do Rio Preto, SP, Brazil.Medicine School of São José do Rio Preto. Department of Infectious Disease. São José do Rio Preto, SP, Brazil.Medicine School of São José do Rio Preto. Department of Gynecology and Obstetrics. São José do Rio Preto, SP, Brazil.Medicine School of Jundiaí. Infectious Pediatric Laboratory. Jundiaí, SP, Brazil.Federal University of São Paulo. Department of Fetal Medicine. São Paulo, SP, Brazil.Father Anchieta University Center. Nursing School. Jundiaí, SP, Brazil.Federal University of São Paulo. Paulista School of Medicine. Departament of Obstetrics. São Paulo, SP, Brazil.Federal University of Goiás. Institute of Tropical Pathology and Public Health. Goiânia, GO, Brazil.Health Secretariat of Goiás State. Maternal and Child Hospital. Goiânia, GO, Brazil.Federal University of São Paulo. Paulista School of Medicine. Departament of Obstetrics. São Paulo, SP, Brazil.Health Secretariat of Goiás State. Maternal and Child Hospital. Goiânia, GO, Brazil.Universidade Federal do Rio Grande do Sul. Hospital das Clinicas de Porto Alegre. Departamento de Genética. Porto Alegre, RS, Brazil.City Hall of Tangará da Serra, Municipal Health Department, Tangará da Serra, MT, Brazil.Federal University of Campina Grande. Medical Academic Unit. Campina Grande, PB, Brazil.Federal University of Campina Grande. Medical Academic Unit. Campina Grande, PB, Brazil.Federal University of Rio de Janeiro. Department of Pediatrics. Rio de Janeiro, RJ, Brazil.D’Or Institute for Research & Education. Department of Pediatrics. Rio de Janeiro, RJ, Brazil.Departmentiversity of Rio de Janeiro Maternity School. Department of Obstectrics. Rio de Janeiro, RJ, Brazil.Departmentiversity of Rio de Janeiro Maternity School. Department of Obstectrics. Rio de Janeiro, RJ, Brazil.Reference Maternity Prof. José Maria de Magalhães Netto. Bahia Health Department, Salvador, BA, Brazil.Oswaldo Cruz Foundation. Gonçalo Moniz Institute. Salvador, BA, Brazil.Oswaldo Cruz Foundation. Gonçalo Moniz Institute. Salvador, BA, Brazil.Federal University of Rio de Janeiro. Department of Infecitous Diseases. Rio de Janeiro, RJ, Brazil.Federal University of Rio de Janeiro. Department of Infecitous Diseases. Rio de Janeiro, RJ, Brazil.Oswaldo Cruz Foundation. Gonçalo Moniz Institute. Salvador, BA, Brazil.Oswaldo Cruz Foundation. Leonidas and Maria Deane Institute. Manaus, AM, Brazil.University of Amazonas State. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil / Doctor Heitor Vieira Dourado Tropical Medicine Foundation. Postgraduate Program in Tropical Medicine. Manaus, AM, Brazil / Oswaldo Cruz Foundation. Leonidas and Maria Deane Institute. Manaus, AM, Brazil.Oswaldo Cruz Foundation. Instituto Nacional de Infectologia Evandro Chagas. Rio de Janeiro, RJ, Brazil.Background: Knowledge regarding the risks associated with Zika virus (ZIKV) infections in pregnancy has relied on individual studies with relatively small sample sizes and variable risk estimates of adverse outcomes, or on surveillance or routinely collected data. Using data from the Zika Brazilian Cohorts Consortium, this study aims, to estimate the risk of adverse outcomes among offspring of women with RT-PCR-confirmed ZIKV infection during pregnancy and to explore heterogeneity between studies. Methods: We performed an individual participant data meta-analysis of the offspring of 1548 pregnant women from 13 studies, using one and two-stage meta-analyses to estimate the absolute risks. Findings: Of the 1548 ZIKV-exposed pregnancies, the risk of miscarriage was 0.9%, while the risk of stillbirth was 0.3%. Among the pregnancies with liveborn children, the risk of prematurity was 10,5%, the risk of low birth weight was 7.7, and the risk of small for gestational age (SGA) was 16.2%. For other abnormalities, the absolute risks were: 2.6% for microcephaly at birth or first evaluation, 4.0% for microcephaly at any time during follow-up, 7.9% for neuroimaging abnormalities, 18.7% for functional neurological abnormalities, 4.0% for ophthalmic abnormalities, 6.4% for auditory abnormalities, 0.6% for arthrogryposis, and 1.5% for dysphagia. This risk was similar in all sites studied and in different socioeconomic conditions, indicating that there are not likely to be other factors modifying this association. Interpretation: This study based on prospectively collected data generates the most robust evidence to date on the risks of congenital ZIKV infections over the early life course. Overall, approximately one-third of liveborn children with prenatal ZIKV exposure presented with at least one abnormality compatible with congenital infection, while the risk to present with at least two abnormalities in combination was less than 1.0%

Current preventive strategies and management of Epstein-Barr virus-related post-transplant lymphoproliferative disease in solid organ transplantation in Europe. Results of the ESGICH Questionnaire-based Cross-sectional Survey

There is limited clinical evidence on the utility of the monitoring of Epstein-Barr virus (EBV) DNAemia in the pre-emptive management of post-transplant lymphoproliferative disease (PTLD) in solid organ transplant (SOT) recipients. We investigated current preventive measures against EBV-related PTLD through a web-based questionnaire sent to 669 SOT programmes in 35 European countries. This study was performed on behalf of the ESGICH study group from the European Society of Clinical Microbiology and Infectious Diseases. A total of 71 SOT programmes from 15 European countries participated in the study. EBV serostatus of the recipient is routinely obtained in 69/71 centres (97%) and 64 (90%) have access to EBV DNAemia assays. EBV monitoring is routinely used in 85.9% of the programmes and 77.4% reported performing pre-emptive treatment for patients with significant EBV DNAemia levels. Pre-emptive treatment for EBV DNAemia included reduction of immunosuppression in 50.9%, switch to mammalian target of rapamycin inhibitors in 30.9%, and use of rituximab in 14.5% of programmes. Imaging by whole-body 18-fluoro-deoxyglucose positron emission tomography (FDG-PET) is used in 60.9% of centres to rule out PTLD and complemented computer tomography is used in 50%. In 10.9% of centres, FDG-PET is included in the first-line diagnostic workup in patients with high-risk EBV DNAemia. Despite the lack of definitive evidence, EBV load measurements are frequently used in Europe to guide diagnostic workup and pre-emptive reduction of immunosuppression. We need prospective and controlled studies to define the impact of EBV monitoring in reducing the risk of PTLD in SOT recipients

Risk of adverse outcomes in offspring with RT-PCR confirmed prenatal Zika virus exposure: an individual participant data meta-analysis of 13 cohorts in the Zika Brazilian Cohorts ConsortiumResearch in context

Summary: Background: Knowledge regarding the risks associated with Zika virus (ZIKV) infections in pregnancy has relied on individual studies with relatively small sample sizes and variable risk estimates of adverse outcomes, or on surveillance or routinely collected data. Using data from the Zika Brazilian Cohorts Consortium, this study aims, to estimate the risk of adverse outcomes among offspring of women with RT-PCR-confirmed ZIKV infection during pregnancy and to explore heterogeneity between studies. Methods: We performed an individual participant data meta-analysis of the offspring of 1548 pregnant women from 13 studies, using one and two-stage meta-analyses to estimate the absolute risks. Findings: Of the 1548 ZIKV-exposed pregnancies, the risk of miscarriage was 0.9%, while the risk of stillbirth was 0.3%. Among the pregnancies with liveborn children, the risk of prematurity was 10,5%, the risk of low birth weight was 7.7, and the risk of small for gestational age (SGA) was 16.2%. For other abnormalities, the absolute risks were: 2.6% for microcephaly at birth or first evaluation, 4.0% for microcephaly at any time during follow-up, 7.9% for neuroimaging abnormalities, 18.7% for functional neurological abnormalities, 4.0% for ophthalmic abnormalities, 6.4% for auditory abnormalities, 0.6% for arthrogryposis, and 1.5% for dysphagia. This risk was similar in all sites studied and in different socioeconomic conditions, indicating that there are not likely to be other factors modifying this association. Interpretation: This study based on prospectively collected data generates the most robust evidence to date on the risks of congenital ZIKV infections over the early life course. Overall, approximately one-third of liveborn children with prenatal ZIKV exposure presented with at least one abnormality compatible with congenital infection, while the risk to present with at least two abnormalities in combination was less than 1.0%. Funding: National Council for Scientific and Technological Development - Brazil (Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq); Wellcome Trust and the United Kingdom's Department for International Development; European Union's Horizon 2020 research and innovation program; Medical Research Council on behalf of the Newton Fund and Wellcome Trust; National Institutes of Health/National Institute of Allergy and Infectious Diseases; Foundation Christophe et Rodolphe Mérieux; Coordination for the improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Capes); Ministry of Health of Brazil; Brazilian Department of Science and Technology; Foundation of Research Support of the State of São Paulo (Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP); Foundation of Research Support of the State of Rio de Janeiro (Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro – FAPERJ); Foundation of Support for Research and Scientific and Technological Development of Maranhão; Evandro Chagas Institute/Brazilian Ministry of Health (Instituto Evandro Chagas/Ministério da Saúde); Foundation of Research Support of the State of Goiás (Fundação de Amparo à Pesquisa do Estado de Goiás – FAPEG); Foundation of Research Support of the State of Rio Grande do Sul (Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul – FAPERGS); Foundation to Support Teaching, Research and Assistance at Hospital das Clínicas, Faculty of Medicine of Ribeirão Preto (Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto); São Paulo State Department of Health (Secretaria de Saúde do Estado de São Paulo); Support Foundation of Pernambuco Science and Technology (Fundação de Amparo à Ciência e Tecnologia de Pernambuco – FACEPE)

New insights into the genetic etiology of Alzheimer’s disease and related dementias

Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele