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Simino J, Shi G, Bis JC, Chasman DI, Ehret GB, Gu X, Guo X, Hwang SJ, Sijbrands E, Smith AV, Verwoert GC, Bragg-Gresham JL, Cadby G, Chen P, Cheng CY, Corre T, de Boer RA, Goel A, Johnson T, Khor CC, Lluís-Ganella C, Luan J, Lyytikäinen LP, Nolte IM, Sim X, Sõber S, van der Most PJ, Verweij N, Zhao JH, Amin N, Boerwinkle E, Bouchard C, Dehghan A, Eiriksdottir G, Elosua R, Franco OH, Gieger C, Harris TB, Hercberg S, Hofman A, James AL, Johnson AD, Kähönen M, Khaw KT, Kutalik Z, Larson MG, Launer LJ, Li G, Liu J, Liu K, Morrison AC, Navis G, Ong RTH, Papanicolau GJ, Penninx BW, Psaty BM, Raffel LJ, Raitakari OT, Rice K, Rivadeneira F, Rose LM, Sanna S, Scott RA, Siscovick DS, Stolk RP, Uitterlinden AG, Vaidya D, van der Klauw MM, Vasan RS, Vithana EN, Völker U, Völzke H, Watkins H, Young TL, Aung T, Bochud M, Farrall M, Hartman CA, Laan M, Lakatta EG, Lehtimäki T, Loos RJF, Lucas G, Meneton P, Palmer LJ, Rettig R, Snieder H, Tai ES, Teo YY, van der Harst P, Wareham NJ, Wijmenga C, Wong TY, Fornage M, Gudnason V, Levy D, Palmas W, Ridker PM, Rotter JI, van Duijn CM, Witteman JCM, Chakravarti A, Rao DC. Gene-age interactions in blood pressure regulation: a large-scale investigation with the CHARGE, Global BPgen, and ICBP Consortia. Am J Hum Genet 2014; 95:24-38. [PMID: 24954895 DOI: 10.1016/j.ajhg.2014.05.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 05/20/2014] [Indexed: 01/11/2023] Open
Abstract
Although age-dependent effects on blood pressure (BP) have been reported, they have not been systematically investigated in large-scale genome-wide association studies (GWASs). We leveraged the infrastructure of three well-established consortia (CHARGE, GBPgen, and ICBP) and a nonstandard approach (age stratification and metaregression) to conduct a genome-wide search of common variants with age-dependent effects on systolic (SBP), diastolic (DBP), mean arterial (MAP), and pulse (PP) pressure. In a two-staged design using 99,241 individuals of European ancestry, we identified 20 genome-wide significant (p ≤ 5 × 10(-8)) loci by using joint tests of the SNP main effect and SNP-age interaction. Nine of the significant loci demonstrated nominal evidence of age-dependent effects on BP by tests of the interactions alone. Index SNPs in the EHBP1L1 (DBP and MAP), CASZ1 (SBP and MAP), and GOSR2 (PP) loci exhibited the largest age interactions, with opposite directions of effect in the young versus the old. The changes in the genetic effects over time were small but nonnegligible (up to 1.58 mm Hg over 60 years). The EHBP1L1 locus was discovered through gene-age interactions only in whites but had DBP main effects replicated (p = 8.3 × 10(-4)) in 8,682 Asians from Singapore, indicating potential interethnic heterogeneity. A secondary analysis revealed 22 loci with evidence of age-specific effects (e.g., only in 20 to 29-year-olds). Age can be used to select samples with larger genetic effect sizes and more homogenous phenotypes, which may increase statistical power. Age-dependent effects identified through novel statistical approaches can provide insight into the biology and temporal regulation underlying BP associations.
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Affiliation(s)
- Jeannette Simino
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Gang Shi
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Joshua C Bis
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA 98101, USA
| | - Daniel I Chasman
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02215, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Georg B Ehret
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Cardiology, Department of Specialties of Internal Medicine, Geneva University Hospitals, Geneva 1211, Switzerland
| | - Xiangjun Gu
- Research Center for Human Genetics, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Xiuqing Guo
- Institute for Translational Genomics and Population Sciences, Los Angeles Biomedical Research Institute and Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Shih-Jen Hwang
- Framingham Heart Study, Framingham, MA 01702, USA; Center for Population Studies, National Heart, Lung, and Blood Institute, Framingham, MA 01702, USA
| | - Eric Sijbrands
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Albert V Smith
- Icelandic Heart Association, 201 Kopavogur, Iceland; Faculty of Medicine, University of Iceland, 101 Reykjavik, Iceland
| | - Germaine C Verwoert
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | | | - Gemma Cadby
- Centre for Genetic Origins of Health and Disease, University of Western Australia, Nedlands, WA 6009, Australia; Genetic Epidemiology and Biostatistics Platform, Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada; Samuel Lunenfeld Research Institute, Toronto, ON M5T 3L9, Canada
| | - Peng Chen
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore
| | - Ching-Yu Cheng
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Ophthalmology, National University Health System, Singapore 119228, Singapore; Singapore Eye Research Institute, Singapore 168751, Singapore; Centre for Quantitative Medicine, Office of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore 169857, Singapore
| | - Tanguy Corre
- Department of Medical Genetics, University of Lausanne, 1005 Lausanne, Switzerland; Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Rudolf A de Boer
- Department of Cardiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Anuj Goel
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Toby Johnson
- Clinical Pharmacology, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Chiea-Chuen Khor
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Ophthalmology, National University Health System, Singapore 119228, Singapore; Division of Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore; Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Paediatrics, National University Health System, Singapore 119074, Singapore
| | - Carla Lluís-Ganella
- Cardiovascular Epidemiology and Genetics, IMIM (Hospital del Mar Medical Research Institute), 08003 Barcelona, Spain
| | - Jian'an Luan
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Leo-Pekka Lyytikäinen
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 30101, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33101, Finland
| | - Ilja M Nolte
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Xueling Sim
- Center for Statistical Genetics, University of Michigan, Ann Arbor, MI 48109, USA; Centre for Molecular Epidemiology, National University of Singapore, Singapore 119260, Singapore
| | - Siim Sõber
- Human Molecular Genetics Group, Institute of Molecular and Cell Biology, University of Tartu, Tartu 51010, Estonia
| | - Peter J van der Most
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Niek Verweij
- Department of Cardiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Jing Hua Zhao
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Najaf Amin
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Eric Boerwinkle
- Human Genetics Center, University of Texas Health Sciences Center, Houston, TX 77225, USA
| | - Claude Bouchard
- Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Abbas Dehghan
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | | | - Roberto Elosua
- Cardiovascular Epidemiology and Genetics, IMIM (Hospital del Mar Medical Research Institute), 08003 Barcelona, Spain; Epidemiology and Public Health Network (CIBERESP), 08036 Barcelona, Spain
| | - Oscar H Franco
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Christian Gieger
- Institute of Genetic Epidemiology, Helmholtz Zentrum München-German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Tamara B Harris
- Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, NIH, Bethesda, MD 20892, USA
| | - Serge Hercberg
- U557 Institut National de la Santé et de la Recherche Médicale, U1125 Institut National de la Recherche Agronomique, Université Paris 13, 93000 Bobigny, France
| | - Albert Hofman
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Alan L James
- Department of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia; School of Medicine and Pharmacology, University of Western Australia, Nedlands, WA 6009, Australia
| | - Andrew D Johnson
- Framingham Heart Study, Framingham, MA 01702, USA; Cardiovascular Epidemiology and Human Genomics Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Mika Kähönen
- Department of Clinical Physiology, Tampere University Hospital, Tampere 33521, Finland; Department of Clinical Physiology, University of Tampere School of Medicine, Tampere 33521, Finland
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Cambridge CB2 2SR, UK
| | - Zoltan Kutalik
- Department of Medical Genetics, University of Lausanne, 1005 Lausanne, Switzerland; Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Martin G Larson
- Framingham Heart Study, Framingham, MA 01702, USA; Department of Mathematics, Boston University, Boston, MA 02215, USA
| | - Lenore J Launer
- Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, NIH, Bethesda, MD 20892, USA
| | - Guo Li
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA 98101, USA
| | - Jianjun Liu
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore; Division of Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Kiang Liu
- Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Alanna C Morrison
- Human Genetics Center, University of Texas Health Sciences Center, Houston, TX 77225, USA
| | - Gerjan Navis
- Department of Internal Medicine, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Rick Twee-Hee Ong
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore
| | - George J Papanicolau
- Division of Cardiovascular Sciences, National Heart, Lung, & Blood Institute, NIH, Bethesda, MD 20892, USA
| | - Brenda W Penninx
- Department of Psychiatry/EMGO Institute/Neuroscience Campus, VU University Medical Centre, 1081 BT Amsterdam, the Netherlands; Department of Psychiatry, Leiden University Medical Centre, 2333 ZD Leiden, the Netherlands; Department of Psychiatry, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Bruce M Psaty
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA 98101, USA; Department of Epidemiology, University of Washington, Seattle, WA 98195, USA; Department of Health Services, University of Washington, Seattle, WA 98195, USA; Group Health Research Institute, Group Health Cooperative, Seattle, WA 98101, USA
| | - Leslie J Raffel
- Medical Genetics Institute, Cedars-Sinai Medical Center, Pacific Theatres, Los Angeles, CA 90048, USA
| | - Olli T Raitakari
- Department of Clinical Physiology and Nuclear Medicine, Turku University Hospital, Turku 20521, Finland; Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku 20521, Finland
| | - Kenneth Rice
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Fernando Rivadeneira
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Lynda M Rose
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02215, USA
| | - Serena Sanna
- Istituto di Ricerca Genetica e Biomedica, CNR, Monserrato 09042, Italy
| | - Robert A Scott
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - David S Siscovick
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA 98101, USA; Department of Epidemiology, University of Washington, Seattle, WA 98195, USA
| | - Ronald P Stolk
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Andre G Uitterlinden
- Department of Internal Medicine, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Netherland Genomics Inititiative, Netherlands Center for Healthy Aging, The Hague 2509, the Netherlands
| | - Dhananjay Vaidya
- Department of Medicine, Johns Hopkins University, Baltimore, MD 21202, USA
| | - Melanie M van der Klauw
- Department of Endocrinology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Ramachandran S Vasan
- Framingham Heart Study, Framingham, MA 01702, USA; Divisions of Epidemiology and Cardiology, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Eranga Nishanthie Vithana
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Ophthalmology, National University Health System, Singapore 119228, Singapore; Singapore Eye Research Institute, Singapore 168751, Singapore; Neuroscience and Behavioural Disorders (NBD) Program, Duke-NUS Graduate Medical School, Singapore 169857, Singapore
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, 17487 Greifswald, Germany
| | - Henry Völzke
- Institute for Community Medicine, University of Greifswald, 17487 Greifswald, Germany
| | - Hugh Watkins
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Terri L Young
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA; Division of Neuroscience, Duke-National University of Singapore, Singapore 169857, Singapore
| | - Tin Aung
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Ophthalmology, National University Health System, Singapore 119228, Singapore; Singapore Eye Research Institute, Singapore 168751, Singapore
| | - Murielle Bochud
- Institute of Social and Preventive Medicine, Lausanne University Hospital, 1010 Lausanne, Switzerland
| | - Martin Farrall
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Catharina A Hartman
- Interdisciplinary Center for Pathology of Emotions, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Maris Laan
- Human Molecular Genetics Group, Institute of Molecular and Cell Biology, University of Tartu, Tartu 51010, Estonia
| | - Edward G Lakatta
- Laboratory of Cardiovascular Science, National Institute on Aging, NIH, Bethesda, MD 21224, USA
| | - Terho Lehtimäki
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 30101, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33101, Finland
| | - Ruth J F Loos
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK; The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; The Genetics of Obesity and Related Metabolic Traits Program, The Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Gavin Lucas
- Cardiovascular Epidemiology and Genetics, IMIM (Hospital del Mar Medical Research Institute), 08003 Barcelona, Spain
| | - Pierre Meneton
- U872 Institut National de la Santé et de la Recherche Médicale, Centre de Recherche des Cordeliers, Paris 75006, France
| | - Lyle J Palmer
- Genetic Epidemiology and Biostatistics Platform, Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada; Samuel Lunenfeld Research Institute, Toronto, ON M5T 3L9, Canada
| | - Rainer Rettig
- Institute of Physiology, University of Greifswald, 17495 Karlsburg, Germany
| | - Harold Snieder
- Department of Epidemiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - E Shyong Tai
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore; Department of Medicine, National University Health System and Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Duke-National University of Singapore Graduate Medical School, Singapore 169857, Singapore
| | - Yik-Ying Teo
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117597, Singapore; Saw Swee Hock School of Public Health, National University Health System, Singapore 117597, Singapore; Life Sciences Institute, National University of Singapore, Singapore 117456, Singapore; Department of Statistics and Applied Probability, National University of Singapore, Singapore 117543, Singapore; Genome Institute of Singapore, A(∗)STAR, Singapore 138672, Singapore
| | - Pim van der Harst
- Department of Cardiology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands; Department of Genetics, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands; Durrer Center for Cardiogenetic Research, 3501 DG Utrecht, the Netherlands
| | - Nicholas J Wareham
- MRC Epidemiology Unit, Institute of Metabolic Science, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Cisca Wijmenga
- Department of Genetics, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, the Netherlands
| | - Tien Yin Wong
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; Department of Ophthalmology, National University Health System, Singapore 119228, Singapore; Singapore Eye Research Institute, Singapore 168751, Singapore
| | - Myriam Fornage
- Research Center for Human Genetics, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX 77030, USA; Human Genetics Center, University of Texas Health Sciences Center, Houston, TX 77225, USA
| | - Vilmundur Gudnason
- Icelandic Heart Association, 201 Kopavogur, Iceland; Faculty of Medicine, University of Iceland, 101 Reykjavik, Iceland
| | - Daniel Levy
- Framingham Heart Study, Framingham, MA 01702, USA; Center for Population Studies, National Heart, Lung, and Blood Institute, Framingham, MA 01702, USA; Boston University School of Medicine, Boston, MA 02118, USA
| | - Walter Palmas
- Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Paul M Ridker
- Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA 02215, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Jerome I Rotter
- Institute for Translational Genomics and Population Sciences, Los Angeles Biomedical Research Institute and Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Cornelia M van Duijn
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Netherland Genomics Inititiative, Netherlands Center for Healthy Aging, The Hague 2509, the Netherlands; Netherland Genomics Initiative, Centre for Medical Systems Biology, 2300 RC Leiden, the Netherlands
| | - Jacqueline C M Witteman
- Department of Epidemiology, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Aravinda Chakravarti
- Center for Complex Disease Genomics, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Dabeeru C Rao
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO 63110, USA; Departments of Psychiatry, Genetics, and Mathematics, Washington University School of Medicine, St. Louis, MO 63110, USA
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