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Sudbury EL, Clifford V, Messina NL, Song R, Curtis N. Mycobacterium tuberculosis-specific cytokine biomarkers to differentiate active TB and LTBI: A systematic review. J Infect 2020; 81:873-881. [PMID: 33007340 DOI: 10.1016/j.jinf.2020.09.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 08/21/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVES New tests are needed to overcome the limitations of existing immunodiagnostic tests for tuberculosis (TB) infection, including their inability to differentiate between active TB and latent TB infection (LTBI). This review aimed to identify the most promising cytokine biomarkers for use as stage-specific markers of TB infection. METHODS A systematic review was done using electronic databases to identify studies that have investigated Mycobacterium tuberculosis (MTB)-specific cytokine responses as diagnostic tools to differentiate between LTBI and active TB. RESULTS The 56 studies included in this systematic review measured the MTB-specific responses of 100 cytokines, the most frequently studied of which were IFN-γ, IL-2, TNF-α, IP-10, IL-10 and IL-13. Ten studies assessed combinations of cytokines, most commonly IL-2 and IFN-γ. For most cytokines, findings were heterogenous between studies. The variation in results likely relates to differences in the study design and laboratory methods, as well as participant and environmental factors. CONCLUSIONS Although several cytokines show promise as stage-specific markers of TB infection, this review highlights the need for further well-designed studies, in both adult and paediatric populations, to establish which cytokine(s) will be of most use in a new generation of immunodiagnostic tests.
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Affiliation(s)
- Eva L Sudbury
- Department of Paediatrics, The University of Melbourne, The Royal Children's Hospital Melbourne, Parkville, Australia; Infectious Diseases Research Group, Murdoch Children's Research Institute, Parkville, Australia.
| | - Vanessa Clifford
- Department of Paediatrics, The University of Melbourne, The Royal Children's Hospital Melbourne, Parkville, Australia; Infectious Diseases Research Group, Murdoch Children's Research Institute, Parkville, Australia; Infectious Diseases Unit, The Royal Children's Hospital, Parkville, Australia.
| | - Nicole L Messina
- Department of Paediatrics, The University of Melbourne, The Royal Children's Hospital Melbourne, Parkville, Australia; Infectious Diseases Research Group, Murdoch Children's Research Institute, Parkville, Australia.
| | - Rinn Song
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the National Institute for Health Research Oxford Biomedical Research Centre, Oxford, UK; Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
| | - Nigel Curtis
- Department of Paediatrics, The University of Melbourne, The Royal Children's Hospital Melbourne, Parkville, Australia; Infectious Diseases Research Group, Murdoch Children's Research Institute, Parkville, Australia; Infectious Diseases Unit, The Royal Children's Hospital, Parkville, Australia.
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Basu Roy R, Sambou B, Sissoko M, Holder B, Gomez MP, Egere U, Sillah AK, Koukounari A, Kampmann B. Protection against mycobacterial infection: A case-control study of mycobacterial immune responses in pairs of Gambian children with discordant infection status despite matched TB exposure. EBioMedicine 2020; 59:102891. [PMID: 32675024 PMCID: PMC7502674 DOI: 10.1016/j.ebiom.2020.102891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Children are particularly susceptible to tuberculosis. However, most children exposed to Mycobacterium tuberculosis are able to control the pathogen without evidence of infection. Correlates of human protective immunity against tuberculosis infection are lacking, and their identification would aid vaccine design. METHODS We recruited pairs of asymptomatic children with discordant tuberculin skin test status but the same sleeping proximity to the same adult with sputum smear-positive tuberculosis in a matched case-control study in The Gambia. Participants were classified as either Highly TB-Exposed Uninfected or Highly TB-Exposed Infected children. Serial luminescence measurements using an in vitro functional auto-luminescent Bacillus Calmette-Guérin (BCG) whole blood assay quantified the dynamics of host control of mycobacterial growth. Assay supernatants were analysed with a multiplex cytokine assay to measure associated inflammatory responses. FINDINGS 29 pairs of matched Highly TB-Exposed Uninfected and Highly TB-Exposed Infected children aged 5 to 15 years old were enroled. Samples from Highly TB-Exposed Uninfected children had higher levels of mycobacterial luminescence at 96 hours than Highly TB-Exposed Infected children. Highly TB-Exposed Uninfected children also produced less BCG-specific interferon-γ than Highly TB-Exposed Infected children at 24 hours and at 96 hours. INTERPRETATION Highly TB-Exposed Uninfected children showed less control of mycobacterial growth compared to Highly TB-Exposed Infected children in a functional assay, whilst cytokine responses mirrored infection status. FUNDING Clinical Research Training Fellowship funded under UK Medical Research Council/Department for International Development Concordat agreement and part of EDCTP2 programme supported by European Union (MR/K023446/1). Also MRC Program Grants (MR/K007602/1, MR/K011944/1, MC_UP_A900/1122).
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Affiliation(s)
- Robindra Basu Roy
- Department of Academic Paediatrics, Section of Paediatric Infectious Disease, Imperial College London, St. Mary's Hospital, Praed Street, London W2 1NY, United Kingdom; Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Basil Sambou
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Muhamed Sissoko
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Beth Holder
- Department of Academic Paediatrics, Section of Paediatric Infectious Disease, Imperial College London, St. Mary's Hospital, Praed Street, London W2 1NY, United Kingdom; Institute of Reproductive and Developmental Biology, Department of Metabolism, Digestion & Reproduction, Imperial College London, Du Cane Road, W12 0HS, United Kingdom
| | - Marie P Gomez
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Uzochukwu Egere
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Department of International Public Health, Liverpool School of Tropical Medicine, Pembroke Place L3 5QA, United Kingdom
| | - Abdou K Sillah
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia
| | - Artemis Koukounari
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, United Kingdom
| | - Beate Kampmann
- Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Road, Fajara, The Gambia; Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom; The Vaccine Centre, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
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Bruiners N, Schurz H, Daya M, Salie M, van Helden PD, Kinnear CJ, Hoal EG, Möller M, Gey van Pittius NC. A regulatory variant in the C1Q gene cluster is associated with tuberculosis susceptibility and C1qA plasma levels in a South African population. Immunogenetics 2020; 72:305-314. [PMID: 32556499 DOI: 10.1007/s00251-020-01167-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/07/2020] [Indexed: 12/11/2022]
Abstract
Several genetic studies have implicated genes that encode for components of the innate immune response in tuberculosis (TB) susceptibility. The complement system is an early player in the innate immune response and provides the host with initial protection by promoting phagocytosis of apoptotic or necrotic cells. The C1q molecule is the first component of the classical pathway that leads to the activation of complement by binding to immune complexes and is encoded by the C1Q gene cluster. We investigated variants in this region to determine its association with TB susceptibility. Five single nucleotide polymorphisms (SNPs) (rs12033074, rs631090, rs172378, rs587585, and rs665691) were genotyped using TaqMan® SNP assays in 456 TB cases and 448 healthy controls and analysed by logistic regression models. The rs587585 variant showed a significant additive allelic association where the minor G allele was found more frequently in TB cases than in controls in both the discovery (p = 0.023; OR = 1.30; 95% CI, 1.04-1.64) and validation cohort (p = 0.038; OR = 1.31; 95% CI, 1.22-1.40). In addition, we detected increased C1qA expression when comparing cases and controls (p = 0.037) and linked this to a dosage effect of the G allele, which increased C1qA expression in TB cases. This is the first study to report the association of C1Q gene polymorphisms with progression to tuberculosis.
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Affiliation(s)
- Natalie Bruiners
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, 07103, USA
| | - Haiko Schurz
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Michelle Daya
- Department of Medicine, University of Colorado Denver, Aurora, CO, 80045, USA
| | - Muneeb Salie
- Department of Genetics, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA
| | - Paul D van Helden
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Craig J Kinnear
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Eileen G Hoal
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Marlo Möller
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Nicolaas C Gey van Pittius
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, SAMRC Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.
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Wu S, Wang MG, Wang Y, He JQ. Polymorphisms of cytokine genes and tuberculosis in two independent studies. Sci Rep 2019; 9:2507. [PMID: 30792445 PMCID: PMC6385216 DOI: 10.1038/s41598-019-39249-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 01/21/2019] [Indexed: 02/06/2023] Open
Abstract
Cytokine gene single nucleotide polymorphisms (SNPs) can influence cytokine levels, which may be associated with tuberculosis (TB) susceptibility. There is evidence that interleukin 1B (IL1B), tumor necrosis factor-alpha (TNF-alpha), and IL6 may be involved in the progression of TB. Using a self-validating case-control design, we selected eleven functional SNPs in IL1B, TNF and IL6 to detect their association with TB in Chinese Han and Tibetan populations. The associations between SNPs and TB were estimated by computing the odds ratios (ORs) and 95% confidence intervals (95% CI) using logistic regression analyses. We found that the IL1B rs16944 polymorphism was associated with decreased risk of TB in the two studies. The G allele at rs2069837 of IL6 was significantly more common in controls than in TB patients in the Han population. Moreover, TNF rs1799964 and rs1800630 were risk factors for susceptibility to TB, which were validated in the Chinese Tibetan population. In addition, TNF rs1799724 and rs1800629 were associated with TB, but only in the Tibetan population. In conclusion, SNPs of the IL1B and TNF gene were associated with TB susceptibility in Chinese Han and Tibetan populations. IL6 polymorphism may be considered as a protective factor for TB in the Chinese Han population, but not the Tibetan population.
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Affiliation(s)
- Shouquan Wu
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Ming-Gui Wang
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yu Wang
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian-Qing He
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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Genetic Polymorphisms of IL1B, IL6, and TNFα in a Chinese Han Population with Pulmonary Tuberculosis. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3010898. [PMID: 29888256 PMCID: PMC5977055 DOI: 10.1155/2018/3010898] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 03/21/2018] [Accepted: 04/08/2018] [Indexed: 02/05/2023]
Abstract
Background The factors that predispose to pulmonary tuberculosis (PTB) are not fully understood. Previous studies have shown that cytokine gene polymorphisms were associated with PTB. Objectives In this study, we have investigated the relationship between ILB, IL6, and TNFα polymorphisms and a predisposition to Mycobacterium tuberculosis (MTB) infection and PTB. Methods A total of 209 cases of PTB, 201 subjects with latent TB infection (LTBI), and 204 healthy controls (HCS) were included in this study. Logistic regression analyses under allelic, homozygous, and heterozygous models were used to calculate P values, odds ratios (ORs), and 95% confidence intervals (CIs) for assessing the association between single nucleotide polymorphisms (SNPs) and disease risk, adjusting for sex and age. Genotyping was conducted using the improved multiplex ligase detection reaction (iMLDR) method. Results When comparing PTB patients with LTBI subjects, significant associations with disease development were observed for SNPs of IL6 and TNFα. When comparing LTBI subjects with HCS, IL1B polymorphisms were significantly associated with LIBI. Haplotype analyses suggested that the CGG haplotype of IL1B was associated with an increased risk of PTB (P = 0.039, OR = 1.34, 95% CI: 1.01–1.76), while the TTGCG haplotype of TNFα was a protective factor against PTB (P = 0.039, OR = 0.66, 95% CI: 0.44–0.98). Conclusion Our study demonstrated that IL1B variants were related to LTBI and IL6 and TNFα variants were associated with PTB.
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Kinnear C, Hoal EG, Schurz H, van Helden PD, Möller M. The role of human host genetics in tuberculosis resistance. Expert Rev Respir Med 2017; 11:721-737. [PMID: 28703045 DOI: 10.1080/17476348.2017.1354700] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Tuberculosis (TB) remains a public health problem: the latest estimate of new incident cases per year is a staggering 10.4 million. Despite this overwhelming number, the majority of the immunocompetent population can control infection with Mycobacterium tuberculosis. The human genome underlies the immune response and contributes to the outcome of TB infection. Areas covered: Investigations of TB resistance in the general population have closely mirrored those of other infectious diseases and initially involved epidemiological observations. Linkage and association studies, including studies of VDR, SLC11A1 and HLA-DRB1 followed. Genome-wide association studies of common variants, not necessarily sufficient for disease, became possible after technological advancements. Other approaches involved the identification of those individuals with rare disease-causing mutations that strongly predispose to TB, epistasis and the role of ethnicity in disease. Despite these efforts, infection outcome, on an individual basis, cannot yet be predicted. Expert commentary: The early identification of future disease progressors is necessary to stem the TB epidemic. Human genetics may contribute to this endeavour and could in future suggest pathways to target for disease prevention. This will however require concerted efforts to establish large, well-phenotyped cohorts from different ethnicities, improved genomic resources and a better understanding of the human genome architecture.
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Affiliation(s)
- Craig Kinnear
- a SAMRC Centre for TB Research, DST/NRF Centre of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences , Stellenbosch University , Cape Town , South Africa
| | - Eileen G Hoal
- a SAMRC Centre for TB Research, DST/NRF Centre of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences , Stellenbosch University , Cape Town , South Africa
| | - Haiko Schurz
- a SAMRC Centre for TB Research, DST/NRF Centre of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences , Stellenbosch University , Cape Town , South Africa
| | - Paul D van Helden
- a SAMRC Centre for TB Research, DST/NRF Centre of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences , Stellenbosch University , Cape Town , South Africa
| | - Marlo Möller
- a SAMRC Centre for TB Research, DST/NRF Centre of Excellence for Biomedical TB Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences , Stellenbosch University , Cape Town , South Africa
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Tsairidou S, Brotherstone S, Coffey M, Bishop SC, Woolliams JA. Quantitative genetic analysis of the bTB diagnostic single intradermal comparative cervical test (SICCT). Genet Sel Evol 2016; 48:90. [PMID: 27884111 PMCID: PMC5123354 DOI: 10.1186/s12711-016-0264-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 11/02/2016] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Bovine tuberculosis (bTB) is a disease of significant economic importance and is a persistent animal health problem with implications for public health worldwide. Control of bTB in the UK has relied on diagnosis through the single intradermal comparative cervical test (SICCT). However, limitations in the sensitivity of this test hinder successful eradication and the control of bTB remains a major challenge. Genetic selection for cattle that are more resistant to bTB infection can assist in bTB control. The aim of this study was to conduct a quantitative genetic analysis of SICCT measurements collected during bTB herd testing. Genetic selection for bTB resistance will be partially informed by SICCT-based diagnosis; therefore it is important to know whether, in addition to increasing bTB resistance, this might also alter genetically the epidemiological characteristics of SICCT. RESULTS Our main findings are that: (1) the SICCT test is robust at the genetic level, since its hierarchy and comparative nature provide substantial protection against random genetic changes that arise from genetic drift and from correlated responses among its components due to either natural or artificial selection; (2) the comparative nature of SICCT provides effective control for initial skin thickness and age-dependent differences; and (3) continuous variation in SICCT is only lowly heritable and has a weak correlation with SICCT positivity among healthy animals which was not significantly different from zero (P > 0.05). These emerging results demonstrate that genetic selection for bTB resistance is unlikely to change the probability of correctly identifying non-infected animals, i.e. the test's specificity, while reducing the overall number of cases. CONCLUSIONS This study cannot exclude all theoretical risks from selection on resistance to bTB infection but the role of SICCT in disease control is unlikely to be rapidly undermined, with any adverse correlated responses expected to be weak and slow, which allow them to be monitored and managed.
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Affiliation(s)
- Smaragda Tsairidou
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG Edinburgh, UK
| | - Susan Brotherstone
- Institute of Evolutionary Biology, University of Edinburgh, King’s Buildings, West Mains Road, EH9 3JT Edinburgh, UK
| | - Mike Coffey
- Animal and Veterinary Sciences, SRUC, Roslin Institute Building, Easter Bush Campus, Midlothian, EH25 9RG Edinburgh, UK
| | - Stephen C. Bishop
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG Edinburgh, UK
| | - John A. Woolliams
- The Roslin Institute and R(D)SVS, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG Edinburgh, UK
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Schrodi SJ. Reflections on the Field of Human Genetics: A Call for Increased Disease Genetics Theory. Front Genet 2016; 7:106. [PMID: 27375680 PMCID: PMC4896932 DOI: 10.3389/fgene.2016.00106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/25/2016] [Indexed: 12/29/2022] Open
Abstract
Development of human genetics theoretical models and the integration of those models with experiment and statistical evaluation are critical for scientific progress. This perspective argues that increased effort in disease genetics theory, complementing experimental, and statistical efforts, will escalate the unraveling of molecular etiologies of complex diseases. In particular, the development of new, realistic disease genetics models will help elucidate complex disease pathogenesis, and the predicted patterns in genetic data made by these models will enable the concurrent, more comprehensive statistical testing of multiple aspects of disease genetics predictions, thereby better identifying disease loci. By theoretical human genetics, I intend to encompass all investigations devoted to modeling the heritable architecture underlying disease traits and studies of the resulting principles and dynamics of such models. Hence, the scope of theoretical disease genetics work includes construction and analysis of models describing how disease-predisposing alleles (1) arise, (2) are transmitted across families and populations, and (3) interact with other risk and protective alleles across both the genome and environmental factors to produce disease states. Theoretical work improves insight into viable genetic models of diseases consistent with empirical results from linkage, transmission, and association studies as well as population genetics. Furthermore, understanding the patterns of genetic data expected under realistic disease models will enable more powerful approaches to discover disease-predisposing alleles and additional heritable factors important in common diseases. In spite of the pivotal role of disease genetics theory, such investigation is not particularly vibrant.
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Affiliation(s)
- Steven J Schrodi
- Marshfield Clinic Research Foundation, Center for Human GeneticsMarshfield, WI, USA; Computation and Informatics in Biology and Medicine, University of Wisconsin-MadisonMadison, WI, USA
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Chheng P, Nsereko M, Malone LL, Okware B, Zalwango S, Joloba M, Boom WH, Mupere E, Stein CM. Tuberculosis case finding in first-degree relative contacts not living with index tuberculosis cases in Kampala, Uganda. Clin Epidemiol 2015; 7:411-9. [PMID: 26508888 PMCID: PMC4610802 DOI: 10.2147/clep.s82389] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To assess the prevalence of pulmonary tuberculosis among first-degree relative (FDR) contacts not living with tuberculosis (TB) cases. METHODS A cross-sectional analysis of household contacts living with an index TB case and FDR contacts living outside of households in Kampala, Uganda, is presented. RESULTS A total of 177 contacts (52 FDRs and 125 index household contacts) of 31 TB cases were examined. Compared with index household contacts, FDR contacts were older, more likely to be TB symptomatic (50% vs 33%), had a higher percentage of abnormal chest X-rays (19% vs 11%), sputum smear positive (15% vs 5%), and many similar epidemiologic risk factors, including HIV infection (13% vs 10%). Contact groups had similar pulmonary tuberculosis prevalence: 9.6% in FDR vs 10.4% in index household contacts and similar Mycobacterium tuberculosis infection: 62% in FDR vs 61% in index households. CONCLUSION TB is common among FDR contacts. High TB prevalence justifies targeting FDRs during household contact investigations. Combining TB active-case finding among FDR contacts with household contact investigation in low-income setting is feasible. This should be part of national TB control program strategies for increasing TB case-detection rates and reducing community TB transmission and death.
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Affiliation(s)
- Phalkun Chheng
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, USA
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - Mary Nsereko
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - LaShaunda L Malone
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - Brenda Okware
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - Sarah Zalwango
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - Moses Joloba
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
- Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda
| | - W Henry Boom
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
| | - Ezekiel Mupere
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, USA
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
- Department of Pediatrics and Child Health, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Catherine M Stein
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, USA
- Uganda-Case Western Reserve University Research Collaboration, Kampala, Uganda
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Mupere E, Malone L, Zalwango S, Okwera A, Nsereko M, Tisch DJ, Parraga IM, Stein CM, Mugerwa R, Boom WH, Mayanja HK, Whalen CC. Wasting among Uganda men with pulmonary tuberculosis is associated with linear regain in lean tissue mass during and after treatment in contrast to women with wasting who regain fat tissue mass: prospective cohort study. BMC Infect Dis 2014; 14:24. [PMID: 24410970 PMCID: PMC3922730 DOI: 10.1186/1471-2334-14-24] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 01/07/2014] [Indexed: 01/10/2023] Open
Abstract
Background Nutritional changes during and after tuberculosis treatment have not been well described. We therefore determined the effect of wasting on rate of mean change in lean tissue and fat mass as measured by bioelectrical impedance analysis (BIA), and mean change in body mass index (BMI) during and after tuberculosis treatment. Methods In a prospective cohort study of 717 adult patients, BMI and height-normalized indices of lean tissue (LMI) and fat mass (FMI) as measured by BIA were assessed at baseline, 3, 12, and 24 months. Results Men with wasting at baseline regained LMI at a greater rate than FMI (4.55 kg/m2 (95% confidence interval (CI): 1.26, 7.83 versus 3.16 (95% CI: 0.80, 5.52)) per month, respectively during initial tuberculosis therapy. In contrast, women with wasting regained FMI at greater rate than LMI (3.55 kg/m2 (95% CI: 0.40, 6.70) versus 2.07 (95% CI: -0.74, 4.88)), respectively. Men with wasting regained BMI at a rate of 6.45 kg/m2 (95% CI: 3.02, 9.87) in the first three months whereas women, had a rate of 3.30 kg/m2 (95% CI: -0.11, 6.72). There were minimal changes in body composition after month 3 and during months 12 to 24. Conclusion Wasted tuberculosis patients regain weight with treatment but the type of gain differs by gender and patients may remain underweight after the initial phase of treatment.
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Affiliation(s)
- Ezekiel Mupere
- Department of Paediatrics & Child Health College of Health Sciences, Makerere University Kampala, Kampala, Uganda.
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Wang JJ, Xia X, Tang SD, Wang J, Deng XZ, Zhang Y, Yue M. Meta-analysis on the associations of TLR2 gene polymorphisms with pulmonary tuberculosis susceptibility among Asian populations. PLoS One 2013; 8:e75090. [PMID: 24124467 PMCID: PMC3790778 DOI: 10.1371/journal.pone.0075090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/11/2013] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Publications regarding the associations of toll-like receptor 2 (TLR2) G2258A and T597C polymorphisms with pulmonary tuberculosis (PTB) susceptibility are inconsistent. A meta-analysis was conducted to investigate the relationship between TLR2 G2258A and T597C polymorphisms with PTB susceptibility. METHODS A systematic search was performed for published studies on the relationship between TLR2 polymorphisms and PTB susceptibility. Information was gathered from each eligible study, and statistically analyzed. RESULTS 6 eligible studies, totaling 1301 cases and 1217 controls on G2258A genotypes, and 8 studies, totaling 2175 cases and 2069 controls on T597C genotypes, were included in the analysis. TLR2 2258G allele and 2258GG genotype were found to be associated with decreased PTB susceptibility (A vs. G: OR = 3.02, 95% CI: 2.22-4.12, P<0.001, GA+AA vs. GG: OR = 2.69, 95% CI = 1.49-4.87, P = 0.001). In the subgroup analyses, the 2258G allele and 2258GG genotype also exhibited a protective effect of PTB risk in Asians (A vs. G: OR = 2.95, 95% CI: 1.91-4.55, P<0.001; GA+AA vs. GG: OR = 3.59, 95% CI: 2.23-5.78, P<0.001), while no associations were observed in Caucasians. No significant associations between T597C polymorphism and PTB were found in the allele model (C vs. T: OR = 0.95, 95% CI: 0.86-1.04, P = 0.28), co-dominant model (CC vs. TT: OR = 0.88, 95% CI = 0.92-1.40, P = 0.25; CT vs. TT: OR = 0.92, 95% CI = 0.80-1.06, P = 0.28), recessive model (CC vs. TT+TC: OR = 0.96, 95% CI: 0.80-1.16, P = 0.69), or dominant model (TC+CC vs. TT: OR = 0.93, 95% CI = 0.76-1.15, P = 0.51). The associations of T597C polymorphism with PTB susceptibility, in the ethnic-specific analyses, were still not significant. CONCLUSION TLR2 2258G allele may provide protective effects against PTB susceptibility, particularly among Asians, whereas TLR2 T597C polymorphism might not be associated with PTB susceptibility.
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Affiliation(s)
- Jia-Jia Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xian Xia
- Department of Nosocomial Infection Control, General Hospital of Beijing Military Region, Beijing, China
| | - Shai-Di Tang
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jie Wang
- Department of General Practice, Kangda College, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-Zhao Deng
- Institute of Disease Control and Prevention, Huadong Research Institute for Medicine and Biotechnics, Nanjing, Jiangsu, China
| | - Yun Zhang
- Institute of Epidemiology and Microbiology, Huadong Research Institute for Medicine and Biotechnics, Nanjing, Jiangsu, China
| | - Ming Yue
- Institute of Epidemiology and Microbiology, Huadong Research Institute for Medicine and Biotechnics, Nanjing, Jiangsu, China
- School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu, China
- * E-mail:
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López Campos GN, Velarde Félix JS, Sandoval Ramírez L, Cázares Salazar S, Corona Nakamura AL, Amaya Tapia G, Prado Montes de Oca E. Polymorphism in cathelicidin gene (CAMP) that alters Hypoxia-inducible factor (HIF-1α::ARNT) binding is not associated with tuberculosis. Int J Immunogenet 2013; 41:54-62. [DOI: 10.1111/iji.12080] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/01/2013] [Accepted: 07/15/2013] [Indexed: 12/27/2022]
Affiliation(s)
- G. N. López Campos
- In silico Laboratory; Pharmaceutical and Medical Biotechnology Unit; Research Center in Technology and Design Assistance of Jalisco State (CIATEJ, AC); National Council of Science and Technology; Guadalajara Mexico
| | - J. S. Velarde Félix
- Biology Academic Unit; Sinaloa Autonomous University (UAS); Culiacán México
- Genomic Medicine Center; Dr. Bernardo J. Gastelum Culiacán Primary Care Hospital; Health Ministry (SS); Culiacán Mexico
| | - L. Sandoval Ramírez
- Genetics Division; Western Biomedical Research Center; National Institute of Social Security (CIBO-IMSS); Guadalajara Mexico
| | - S. Cázares Salazar
- Biology and Chemistry Sciences Faculty; Sinaloa Autonomous University (FCQB-UAS); Culiacán Mexico
| | - A. L. Corona Nakamura
- Infectology Service; External Attention Medical Unit (UMAE); Western National Medical Center (CMNO); Specialty Hospital; National Institute of Social Security (IMSS); Guadalajara Mexico
| | - G. Amaya Tapia
- Infectology Service; Primary Care Western Hospital; Health Ministry of Jalisco State (SSJ); Guadalajara Mexico
| | - E. Prado Montes de Oca
- In silico Laboratory; Pharmaceutical and Medical Biotechnology Unit; Research Center in Technology and Design Assistance of Jalisco State (CIATEJ, AC); National Council of Science and Technology; Guadalajara Mexico
- Molecular Biology Laboratory; Biosecurity Area, Pharmaceutical and Medical Biotechnology Unit; Research Center in Technology and Design Assistance of Jalisco State (CIATEJ, AC); National Council of Science and Technology (CONACYT); Guadalajara Mexico
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13
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Cobat A, Hoal EG, Gallant CJ, Simkin L, Black GF, Stanley K, Jaïs JP, Yu TH, Boland-Auge A, Grange G, Delacourt C, van Helden P, Casanova JL, Abel L, Alcaïs A, Schurr E. Identification of a major locus, TNF1, that controls BCG-triggered tumor necrosis factor production by leukocytes in an area hyperendemic for tuberculosis. Clin Infect Dis 2013; 57:963-70. [PMID: 23800941 DOI: 10.1093/cid/cit438] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Tumor necrosis factor (TNF) is a key immune regulator of tuberculosis resistance, as exemplified by the highly increased risk of tuberculosis disease among individuals receiving TNF-blocker therapy. METHODS We determined the extent of TNF production after stimulation with BCG or BCG plus interferon gamma (IFN-γ) using a whole blood assay in 392 children belonging to 135 nuclear families from an area hyperendemic for tuberculosis in South Africa. We conducted classical univariate and bivariate genome-wide linkage analysis of TNF production using the data from both stimulation protocols by means of an extension of the maximum-likelihood-binomial method for quantitative trait loci to multivariate analysis. RESULTS Stimulation of whole blood by either BCG or BCG plus IFN-γ resulted in a range of TNF release across subjects. Extent of TNF production following both stimulation protocols was highly correlated (r = 0.81). We failed to identify genetic linkage of TNF release when considering each stimulus separately. However, using a multivariate approach, we detected a major pleiotropic locus (P < 10(-5)) on chromosome region 11p15, termed TNF locus 1 (TNF1), that controlled TNF production after stimulation by both BCG alone and BCG plus IFN-γ. CONCLUSIONS The TNF1 locus was mapped in the vicinity of the TST1 locus, previously identified in the same family sample, that controls tuberculin skin test (TST) negativity per se, that is, T-cell-independent resistance to Mycobacterium tuberculosis infection. This suggested that there is a connection between TST negativity per se and TNF production.
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Affiliation(s)
- Aurelie Cobat
- McGill International TB Centre and Departments of Human Genetics and Medicine, McGill University, Montreal, Quebec, Canada
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Stein CM, Hall NB, Malone LL, Mupere E. The household contact study design for genetic epidemiological studies of infectious diseases. Front Genet 2013; 4:61. [PMID: 23641253 PMCID: PMC3639375 DOI: 10.3389/fgene.2013.00061] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/05/2013] [Indexed: 11/17/2022] Open
Abstract
Most genetic epidemiological study designs fall into one of two categories: family based and population-based (case–control). However, recent advances in statistical genetics call for study designs that combine these two approaches. We describe the household contact study design as we have applied it in our several years of study of the epidemiology of tuberculosis. Though we highlight its applicability for genetic epidemiological studies of infectious diseases, there are many facets of this design that are appealing for modern genetic studies, including the simultaneous enrollment of related and unrelated individuals, closely and distantly related individuals, collection of extensive epidemiologic and phenotypic data, and evaluation of effects of shared environment and gene by environment interaction. These study design characteristics are particularly appealing for current sequencing studies.
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Affiliation(s)
- Catherine M Stein
- Department of Epidemiology and Biostatistics, Case Western Reserve University Cleveland, OH, USA ; Uganda - Case Western Reserve University Research Collaboration Kampala, Uganda
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15
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Tao L, Zalwango S, Chervenak K, Thiel B, Malone LL, Qiu F, Mayanja-Kizza H, Boom WH, Stein CM. Genetic and shared environmental influences on interferon-γ production in response to Mycobacterium tuberculosis antigens in a Ugandan population. Am J Trop Med Hyg 2013; 89:169-73. [PMID: 23629934 DOI: 10.4269/ajtmh.12-0670] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Interferon-γ (IFN-γ) is a key cytokine in the immune response to Mycobacterium tuberculosis (Mtb). Many studies established IFN-γ responses are influenced by host genetics, however differed widely by the study design and heritability estimation method. We estimated heritability of IFN-γ responses to Mtb culture filtrate (CF), ESAT-6, and Antigen 85B (Ag85B) in 1,104 Ugandans from a household contact study. Our method separately evaluates shared environmental and genetic variance, therefore heritability estimates were not upwardly biased, ranging from 11.6% for Ag85B to 22.9% for CF. Subset analyses of individuals with latent Mtb infection or without human immunodeficiency virus infection yielded higher heritability estimates, suggesting 10-30% of variation in IFN-γ is caused by a shared environment. Immunosuppression does not negate the role of genetics on IFN-γ response. These estimates are remarkably close to those reported for components of the innate immune response. These findings have implications for the interpretation of IFN-γ response assays and vaccine studies.
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Affiliation(s)
- Li Tao
- Department of Medicine, Case Western Reserve University, Cleveland, OH, USA.
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16
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Baker AR, Qiu F, Randhawa AK, Horne DJ, Adams MD, Shey M, Barnholtz-Sloan J, Mayanja-Kizza H, Kaplan G, Hanekom WA, Boom WH, Hawn TR, Stein CM. Genetic variation in TLR genes in Ugandan and South African populations and comparison with HapMap data. PLoS One 2012; 7:e47597. [PMID: 23112821 PMCID: PMC3480404 DOI: 10.1371/journal.pone.0047597] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 09/18/2012] [Indexed: 11/25/2022] Open
Abstract
Genetic epidemiological studies of complex diseases often rely on data from the International HapMap Consortium for identification of single nucleotide polymorphisms (SNPs), particularly those that tag haplotypes. However, little is known about the relevance of the African populations used to collect HapMap data for study populations conducted elsewhere in Africa. Toll-like receptor (TLR) genes play a key role in susceptibility to various infectious diseases, including tuberculosis. We conducted full-exon sequencing in samples obtained from Uganda (n = 48) and South Africa (n = 48), in four genes in the TLR pathway: TLR2, TLR4, TLR6, and TIRAP. We identified one novel TIRAP SNP (with minor allele frequency [MAF] 3.2%) and a novel TLR6 SNP (MAF 8%) in the Ugandan population, and a TLR6 SNP that is unique to the South African population (MAF 14%). These SNPs were also not present in the 1000 Genomes data. Genotype and haplotype frequencies and linkage disequilibrium patterns in Uganda and South Africa were similar to African populations in the HapMap datasets. Multidimensional scaling analysis of polymorphisms in all four genes suggested broad overlap of all of the examined African populations. Based on these data, we propose that there is enough similarity among African populations represented in the HapMap database to justify initial SNP selection for genetic epidemiological studies in Uganda and South Africa. We also discovered three novel polymorphisms that appear to be population-specific and would only be detected by sequencing efforts.
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Affiliation(s)
- Allison R. Baker
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Feiyou Qiu
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - April Kaur Randhawa
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - David J. Horne
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Mark D. Adams
- Department of Genetics and Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Muki Shey
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Diseases and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, South Africa
| | - Jill Barnholtz-Sloan
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Harriet Mayanja-Kizza
- Uganda – Case Western Reserve University Research Collaboration, Cleveland, Ohio, United States of America, and Kampala, Uganda
- Makerere University School of Medicine and Mulago Hospital, Kampala, Uganda
| | - Gilla Kaplan
- Public Health Research Institute, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, United States of America
| | - Willem A. Hanekom
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Diseases and Molecular Medicine and School of Child and Adolescent Health, University of Cape Town, South Africa
| | - W. Henry Boom
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Uganda – Case Western Reserve University Research Collaboration, Cleveland, Ohio, United States of America, and Kampala, Uganda
| | - Thomas R. Hawn
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Catherine M. Stein
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
- Uganda – Case Western Reserve University Research Collaboration, Cleveland, Ohio, United States of America, and Kampala, Uganda
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17
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Mupere E, Malone L, Zalwango S, Chiunda A, Okwera A, Parraga I, Stein CM, Tisch DJ, Mugerwa R, Boom WH, Mayanja H, Whalen CC. Lean tissue mass wasting is associated with increased risk of mortality among women with pulmonary tuberculosis in urban Uganda. Ann Epidemiol 2012; 22:466-73. [PMID: 22575813 DOI: 10.1016/j.annepidem.2012.04.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 02/06/2012] [Accepted: 04/14/2012] [Indexed: 01/10/2023]
Abstract
OBJECTIVES We assessed the impact of wasting on survival in patients with tuberculosis by using a precise height-normalized lean tissue mass index (LMI) estimated by bioelectrical impedance analysis and body mass index (BMI). METHODS In a retrospective cohort study, 747 adult pulmonary patients with tuberculosis who were screened for HIV and nutritional status were followed for survival. RESULTS Of 747 patients, 310 had baseline wasting by BMI (kg/m(2)) and 103 by LMI (kg/m(2)). Total deaths were 105. Among men with reduced BMI, risk of death was 70% greater (hazard ratio [HR] 1.7, 95% confidence interval [95% CI] 1.03-2.81) than in men with normal BMI. Survival did not differ by LMI among men (HR 1.1; 95% CI 0.5-2.9). In women, both the BMI and LMI were associated with survival. Among women with reduced BMI, risk of death was 80% greater (HR 1.8; 95% CI 0.9-3.5) than in women with normal BMI; risk of death was 5-fold greater (HR 5.0; 95% CI 1.6-15.9) for women with low LMI compared with women with normal LMI. CONCLUSIONS Wasting assessed by reduced BMI is associated with an increased risk for death among both men and women whereas reduced LMI is among women with tuberculosis.
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Affiliation(s)
- Ezekiel Mupere
- Department of Paediatrics & Child Health, College of Health Sciences, Makerere University Kampala, Uganda.
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18
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Baker AR, Zalwango S, Malone LL, Igo RP, Qiu F, Nsereko M, Adams MD, Supelak P, Mayanja-Kizza H, Boom WH, Stein CM. Genetic susceptibility to tuberculosis associated with cathepsin Z haplotype in a Ugandan household contact study. Hum Immunol 2011; 72:426-30. [PMID: 21354459 DOI: 10.1016/j.humimm.2011.02.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Revised: 01/14/2011] [Accepted: 02/22/2011] [Indexed: 11/28/2022]
Abstract
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), causes 9 million new cases worldwide and 2 million deaths annually. Genetic linkage and association analyses have suggested several chromosomal regions and candidate genes involved in TB susceptibility. This study examines the association of TB disease susceptibility with a selection of biologically relevant genes on regions on chromosomes 7 (IL6 and CARD11) and 20 (CTSZ and MC3R) and fine mapping of the chromosome 7p22-p21 region identified through our genome scan. We analyzed 565 individuals from Kampala, Uganda, who were previously included in our genome-wide linkage scan. Association analyses were conducted for 1,417 single-nucleotide polymorphisms (SNP) that passed quality control. None of the candidate gene or fine mapping SNPs was significantly associated with TB susceptibility (p > 0.10). When we restricted the analysis to HIV-negative individuals, 2 SNPs on chromosome 7 were significantly associated with TB susceptibility (p < 0.05). Haplotype analyses identified a significant risk haplotype in cathepsin X (CTSZ; p = 0.0281, odds ratio = 1.5493, 95% confidence interval [1.039, 2.320]).
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Affiliation(s)
- Allison R Baker
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, USA
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19
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Oki NO, Motsinger-Reif AA, Antas PRZ, Levy S, Holland SM, Sterling TR. Novel human genetic variants associated with extrapulmonary tuberculosis: a pilot genome wide association study. BMC Res Notes 2011; 4:28. [PMID: 21281516 PMCID: PMC3041678 DOI: 10.1186/1756-0500-4-28] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 01/31/2011] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Approximately 5-10% of persons infected with M. tuberculosis develop tuberculosis, but the factors associated with disease progression are incompletely understood. Both linkage and association studies have identified human genetic variants associated with susceptibility to pulmonary tuberculosis, but few genetic studies have evaluated extrapulmonary disease. Because extrapulmonary and pulmonary tuberculosis likely have different underlying pathophysiology, identification of genetic mutations associated with extrapulmonary disease is important. FINDINGS We performed a pilot genome-wide association study among 24 persons with previous extrapulmonary tuberculosis and well-characterized immune defects; 24 pulmonary tuberculosis patients and 57 patients with M. tuberculosis infection served as controls. The Affymetrix GeneChip Human Mapping Xba Array was used for genotyping; after careful quality control, genotypes at 44,175 single nucleotide polymorphisms (SNPs) were available for analysis. Eigenstrat quantified population stratification within our sample; logistic regression, using results of the Eigenstrat analysis as a covariate, identified significant associations between groups. Permutation testing controlled the family-wise error rate for each comparison between groups. Four SNPs were significantly associated with extrapulmonary tuberculosis compared to controls with M. tuberculosis infection; one (rs4893980) in the gene PDE11A, one (rs10488286) in KCND2, and one (rs2026414) in PCDH15; one was in chromosome 7 but not associated with a known gene. Two additional variants were significantly associated with extrapulmonary tuberculosis compared with pulmonary tuberculosis; one (rs340708) in the gene FAM135B and one in chromosome 13 but not associated with a known gene. The function of all four genes affects cell signaling and activity, including in the brain. CONCLUSIONS In this pilot study, we identified 6 novel variants not previously known to be associated with extrapulmonary tuberculosis, including two SNPs more common in persons with extrapulmonary than pulmonary tuberculosis. This provides some support for the hypothesis that the pathogenesis and genetic predisposition to extrapulmonary tuberculosis differs from pulmonary tuberculosis. Further study of these novel SNPs, and more well-powered genome-wide studies of extrapulmonary tuberculosis, is warranted.
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Affiliation(s)
- Noffisat O Oki
- Bioinformatics Research Center, Department of Statistics, North Carolina State University, Raleigh, NC, USA
| | - Alison A Motsinger-Reif
- Bioinformatics Research Center, Department of Statistics, North Carolina State University, Raleigh, NC, USA
| | - Paulo RZ Antas
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Shawn Levy
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Steven M Holland
- Laboratory of Clinical Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Timothy R Sterling
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
- Center for Health Services Research, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
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Abstract
Several candidate gene studies have provided evidence for a role of host genetics in susceptibility to tuberculosis (TB). However, the results of these studies have been very inconsistent, even within a study population. Here, we review the design of these studies from a genetic epidemiological perspective, illustrating important differences in phenotype definition in both cases and controls, consideration of latent M. tuberculosis infection versus active TB disease, population genetic factors such as population substructure and linkage disequilibrium, polymorphism selection, and potential global differences in M. tuberculosis strain. These considerable differences between studies should be accounted for when examining the current literature. Recommendations are made for future studies to further clarify the host genetics of TB.
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Affiliation(s)
- Catherine M Stein
- Department of Epidemiology and Biostatistics, and Tuberculosis Research Unit, Case Western Reserve University, Cleveland, Ohio, United States of America.
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21
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Liu C, Wang J, Zhou S, Wang B, Ma X. Association between -238 but not -308 polymorphism of Tumor necrosis factor alpha (TNF-alpha)v and unexplained recurrent spontaneous abortion (URSA) in Chinese population. Reprod Biol Endocrinol 2010; 8:114. [PMID: 20920206 PMCID: PMC2956720 DOI: 10.1186/1477-7827-8-114] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 09/28/2010] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVES TNF-alpha is a critical cytokine produced by Th1 cells while altered T helper 1 (Th1)-Th2 balance is found crucial for a successful pregnancy. STUDY DESIGN A cohort of 132 Southern Chinese Han RSA patients and 152 controls constituted the subjects of this study. Two functional polymorphisms -308 and -238 of TNF-alpha were studied by association analysis. RESULTS lack of association was found in TNF-alpha -308 SNP yet a significant difference was discovered in -238 polymorphism. CONCLUSION This study suggested that TNF-alpha may be a risk factor in Chinese RSA patients. However the ethnic differences may also contribute to the results.
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Affiliation(s)
- Chunmei Liu
- National Research Institute for Family Planning, Beijing, 100081 China
- Peking Union Medical College, Beijing, China
| | - Jing Wang
- National Research Institute for Family Planning, Beijing, 100081 China
- Peking Union Medical College, Beijing, China
| | - Sirui Zhou
- National Research Institute for Family Planning, Beijing, 100081 China
- Peking Union Medical College, Beijing, China
| | - Binbin Wang
- National Research Institute for Family Planning, Beijing, 100081 China
- Peking Union Medical College, Beijing, China
| | - Xu Ma
- National Research Institute for Family Planning, Beijing, 100081 China
- Peking Union Medical College, Beijing, China
- World Health Organization Collaborating Centre for Research in Human Reproduction, Beijing, China
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Möller M, Hoal EG. Current findings, challenges and novel approaches in human genetic susceptibility to tuberculosis. Tuberculosis (Edinb) 2010; 90:71-83. [PMID: 20206579 DOI: 10.1016/j.tube.2010.02.002] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 02/03/2010] [Indexed: 12/22/2022]
Abstract
The evidence for a human genetic component in susceptibility to tuberculosis (TB) is incontrovertible. Quite apart from studies of rare disease events illustrating the importance of key genes in humans and animals, TB at the population level is also influenced by the genetics of the host. Heritability of disease concordance and immune responses to mycobacterial antigens has been clearly shown, and ranges up to 71%. Linkage studies, designed to identify major susceptibility genes in a disease, have produced a number of candidate loci but few, except for regions on chromosome 5p15, 20p and 20q, have been replicated. The region on 5p15 regulates the intensity of the response to the tuberculin skin test, and another locus on 11p14 appears to control resistance to the bacterium. In addition, numerous genes and pathways have been implicated in candidate gene association studies, with validation of polymorphisms in IFNG, NRAMP1, and NOS2A and equivocal results for IL10, CCL2, DC-SIGN, P2RX7, VDR, TLR2, TLR9 and SP110. Other more recently researched candidate genes such as TNFRSF1B remain to be validated, preferably in meta-analyses. New approaches have provided early evidence for the importance of gene-gene interactions in regulating resistance to disease, and also the prospect that applying host genetics in the field of vaccinomics could lead to a more targeted approach in designing interventions to aid the human immune system in combating mycobacteria. Genome-wide association studies and admixture mapping are approaches that remain to be applied to TB, and it is not clear, as is the case with other complex diseases, how much of the heritability of the TB susceptibility phenotype will be determined by multiple genes of small effect versus rare variants with disproportionately large effects.
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Affiliation(s)
- Marlo Möller
- Molecular Biology and Human Genetics, MRC Centre for Molecular and Cellular Biology and the DST/NRF Centre of Excellence for Biomedical TB Research, Faculty of Health Sciences, P.O. Box 19063, Stellenbosch University, Tygerberg 7505, South Africa
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Capparelli R, Palumbo D, Iannaccone M, Iannelli D. Human V-ATPase gene can protect or predispose the host to pulmonary tuberculosis. Genes Immun 2009; 10:641-6. [PMID: 19536151 DOI: 10.1038/gene.2009.48] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Patients (305 patients with pulmonary tuberculosis) and controls (290 household genetically unrelated contacts) were tested by polymerase chain reaction (PCR) for polymorphisms in the intron 15 and the 5' untranslated region of the gene coding for the a3 isoform of the human ATPase gene. Diagnosis of pulmonary tuberculosis was based on chest radiography and sputum smear examination and confirmed by PCR and bacteriological tests. Alleles (two at each site) segregated in the form of four haplotype pairs: 13, 14 (very rare), 23, and 24. The 13/24 (double heterozygous) patients were protected against tuberculosis (OR: 0.15; P: 10(-8); CI: 0.08-0.3). The 13/13 vs 13/24 and 23/23 vs 23/24 (double homozygous) patients were susceptible to the disease (OR. 5.8; P: 6 x 10(-7); CI: 2.8-11.9; OR: 4.5; P: 5 x 10(-7); CI: 2.5-8.4, respectively).
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Affiliation(s)
- R Capparelli
- Faculty of Biotechnology, University of Naples, Federico II, Portici, Naples, Italy
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Stein CM, Zalwango S, Malone LL, Won S, Mayanja-Kizza H, Mugerwa RD, Leontiev DV, Thompson CL, Cartier KC, Elston RC, Iyengar SK, Boom WH, Whalen CC. Genome scan of M. tuberculosis infection and disease in Ugandans. PLoS One 2008; 3:e4094. [PMID: 19116662 PMCID: PMC2605555 DOI: 10.1371/journal.pone.0004094] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Accepted: 11/25/2008] [Indexed: 01/25/2023] Open
Abstract
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is an enduring public health problem globally, particularly in sub-Saharan Africa. Several studies have suggested a role for host genetic susceptibility in increased risk for TB but results across studies have been equivocal. As part of a household contact study of Mtb infection and disease in Kampala, Uganda, we have taken a unique approach to the study of genetic susceptibility to TB, by studying three phenotypes. First, we analyzed culture confirmed TB disease compared to latent Mtb infection (LTBI) or lack of Mtb infection. Second, we analyzed resistance to Mtb infection in the face of continuous exposure, defined by a persistently negative tuberculin skin test (PTST-); this outcome was contrasted to LTBI. Third, we analyzed an intermediate phenotype, tumor necrosis factor-alpha (TNFalpha) expression in response to soluble Mtb ligands enriched with molecules secreted from Mtb (culture filtrate). We conducted a full microsatellite genome scan, using genotypes generated by the Center for Medical Genetics at Marshfield. Multipoint model-free linkage analysis was conducted using an extension of the Haseman-Elston regression model that includes half sibling pairs, and HIV status was included as a covariate in the model. The analysis included 803 individuals from 193 pedigrees, comprising 258 full sibling pairs and 175 half sibling pairs. Suggestive linkage (p<10(-3)) was observed on chromosomes 2q21-2q24 and 5p13-5q22 for PTST-, and on chromosome 7p22-7p21 for TB; these findings for PTST- are novel and the chromosome 7 region contains the IL6 gene. In addition, we replicated recent linkage findings on chromosome 20q13 for TB (p = 0.002). We also observed linkage at the nominal alpha = 0.05 threshold to a number of promising candidate genes, SLC11A1 (PTST- p = 0.02), IL-1 complex (TB p = 0.01), IL12BR2 (TNFalpha p = 0.006), IL12A (TB p = 0.02) and IFNGR2 (TNFalpha p = 0.002). These results confirm not only that genetic factors influence the interaction between humans and Mtb but more importantly that they differ according to the outcome of that interaction: exposure but no infection, infection without progression to disease, or progression of infection to disease. Many of the genetic factors for each of these stages are part of the innate immune system.
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Affiliation(s)
- Catherine M. Stein
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
- Tuberculosis Research Unit, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Uganda – CWRU Research Collaboration, Kampala, Uganda
| | | | - LaShaunda L. Malone
- Tuberculosis Research Unit, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Sungho Won
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Harriet Mayanja-Kizza
- Uganda – CWRU Research Collaboration, Kampala, Uganda
- Makerere University School of Medicine and Mulago Hospital, Kampala, Uganda
| | - Roy D. Mugerwa
- Uganda – CWRU Research Collaboration, Kampala, Uganda
- Makerere University School of Medicine and Mulago Hospital, Kampala, Uganda
| | - Dmitry V. Leontiev
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Cheryl L. Thompson
- Department of Family Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Kevin C. Cartier
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Robert C. Elston
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Sudha K. Iyengar
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - W. Henry Boom
- Tuberculosis Research Unit, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Uganda – CWRU Research Collaboration, Kampala, Uganda
| | - Christopher C. Whalen
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio, United States of America
- Tuberculosis Research Unit, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Uganda – CWRU Research Collaboration, Kampala, Uganda
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Aukes MF, Alizadeh BZ, Sitskoorn MM, Selten JP, Sinke RJ, Kemner C, Ophoff RA, Kahn RS. Finding suitable phenotypes for genetic studies of schizophrenia: heritability and segregation analysis. Biol Psychiatry 2008; 64:128-36. [PMID: 18295748 DOI: 10.1016/j.biopsych.2007.12.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 12/20/2007] [Accepted: 12/28/2007] [Indexed: 02/01/2023]
Abstract
BACKGROUND Schizophrenia is a highly heritable and complex disorder. Multiple genes are likely to be involved, complicating genetic research into the etiology of this disorder. Intermediate phenotypes or endophenotypes may facilitate genetic research if they display a simpler mode of transmission than schizophrenia itself, i.e., if they reflect more closely the underlying genetic effects. METHODS Twenty-five multigenerational families with multiple members affected with schizophrenia (180 subjects) were administered an extensive neuropsychological, psychophysiological, and personality test battery. Familial correlations were calculated to select heritable traits. Subsequent heritability analysis followed by commingling and segregation analysis were performed to unravel the pattern of transmission and to estimate heritability. RESULTS Five traits, including sensorimotor gating, openness, verbal fluency, early visual perception, and spatial working memory, showed moderate familial correlations. Heritability estimates for these traits ranged from 37% to 54%. A major gene model resembling dominant transmission was found for both sensorimotor gating and openness. Verbal fluency, early visual perception, and spatial working memory may be accounted for by polygenic, multifactorial, or environmental effects. CONCLUSIONS Only 2 of 13 candidate endophenotypes showed a simple mode of transmission useful for successful application in molecular genetic research: sensorimotor gating and openness. To our knowledge, this is the first study to investigate the pattern of transmission for these traits.
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Affiliation(s)
- Maartje F Aukes
- Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands.
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van der Eijk EA, van de Vosse E, Vandenbroucke JP, van Dissel JT. Heredity versus environment in tuberculosis in twins: the 1950s United Kingdom Prophit Survey Simonds and Comstock revisited. Am J Respir Crit Care Med 2007; 176:1281-8. [PMID: 17823356 DOI: 10.1164/rccm.200703-435oc] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE In his 1978 article on tuberculosis (TB) in twins, Comstock concluded that the 2.5-fold higher concordance rate for TB among monozygotic versus dizygotic twins in the Prophit survey of the 1950s implicated inherited susceptibility as a major risk factor for TB in humans. His analysis did not take into account strong imbalance of variables within subgroups, underestimating possible confounding effects of environmental factors. OBJECTIVES To reconsider the role of environmental versus hereditary factors in determining the concordance rate of TB among twin pairs. METHODS Reanalysis of the Prophit Survey. MEASUREMENTS AND MAIN RESULTS A known Mycobacterium tuberculosis-positive or M. tuberculosis-negative sputum in the index TB case markedly influenced the odds ratio (OR) of concordance in the twin pairs. In 87 pairs with co-twins exposed to a sputum-negative index case, monozygotic and dizygotic twins did not differ in concordance for TB (OR, 1.1; 95% confidence interval [95% CI], 0.4-2.8). A higher concordance rate for TB among monozygotic versus dizygotic twins was confined to 106 pairs with the co-twins exposed to a sputum-positive index case (OR, 3.4; 95% CI, 1.6-7.2), and was highest in adolescent twins living together. ORs of TB concordance were proportional to intensity of exposure (sputum smear positivity, physical proximity between twin pairs, contagiousness of disease, and living together) rather than to zygosity. CONCLUSIONS In the Prophit survey of susceptibility to TB among twins, environmental factors (i.e., intensity of exposure to tubercle bacilli) outweigh the importance of hereditary factors. Environmental factors and the context of transmission should be given more emphasis when studying interindividual and population differences in susceptibility to infectious diseases such as TB.
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Affiliation(s)
- Ellen A van der Eijk
- Department of Infectious Diseases, C5-P, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands
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Stein CM, Zalwango S, Chiunda AB, Millard C, Leontiev DV, Horvath AL, Cartier KC, Chervenak K, Boom WH, Elston RC, Mugerwa RD, Whalen CC, Iyengar SK. Linkage and association analysis of candidate genes for TB and TNFalpha cytokine expression: evidence for association with IFNGR1, IL-10, and TNF receptor 1 genes. Hum Genet 2007; 121:663-73. [PMID: 17431682 DOI: 10.1007/s00439-007-0357-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Accepted: 03/16/2007] [Indexed: 01/29/2023]
Abstract
Tuberculosis (TB) is a growing public health threat globally and several studies suggest a role of host genetic susceptibility in increased TB risk. As part of a household contact study in Kampala, Uganda, we have taken a unique approach to the study of genetic susceptibility to TB by developing an intermediate phenotype model for TB susceptibility, analyzing levels of tumor necrosis factor-alpha (TNFalpha) in response to culture filtrate as the phenotype. In the present study, we analyzed candidate genes related to TNFalpha regulation and found that interleukin (IL)-10, interferon-gamma receptor 1 (IFNGR1), and TNFalpha receptor 1 (TNFR1) genes were linked and associated to both TB and TNFalpha. We also show that these associations are with progression to active disease and not susceptibility to latent infection. This is the first report of an association between TB and TNFR1 in a human population and our findings for IL-10 and IFNGR1 replicate previous findings. By observing pleiotropic effects on both phenotypes, we show construct validity of our intermediate phenotype model, which enables the characterization of the role of these genetic polymorphisms on TB pathogenesis. This study further illustrates the utility of such a model for disentangling complex traits.
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Affiliation(s)
- Catherine M Stein
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Wolstein Research Building Room 1303, 2103 Cornell Rd, Cleveland, OH 44106, USA
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Nolan D, Gaudieri S, Mallal S. Host genetics and viral infections: immunology taught by viruses, virology taught by the immune system. Curr Opin Immunol 2006; 18:413-21. [PMID: 16777398 DOI: 10.1016/j.coi.2006.05.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Accepted: 05/31/2006] [Indexed: 10/24/2022]
Abstract
Viruses are prototypic obligate intracellular pathogens, and are therefore, by necessity, highly pre-adapted to surviving the host immune response. Nevertheless, host genetic factors remain an important determinant of disease outcome, particularly in the case of viruses that have encountered humans in the more recent past (e.g. human immunodeficiency virus). Recent studies have identified an increasingly rich network of functionally relevant polymorphic immune factors, including major MHC alleles, killer immunoglobulin-like receptors and functional chemokine receptor polymorphisms. Moreover, genetic variation is increasingly appreciated beyond the single genotype level, incorporating extended haplotypes as well as regions of segmental genetic duplication. These issues can be considered within an evolutionary perspective that acknowledges the crucial role of adaptive host-viral relationships in shaping both host and pathogen genetic diversity.
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Affiliation(s)
- David Nolan
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Level 2, North Block, Perth, Western Australia
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