Prof. E.M. Derks PhD

All Publications

EDUCATION

2001-2006:
PhD (cum laude), title thesis “Assessment and Genetic Aetiology of Attention Problems, Hyperactivity, and Related Disorders”, at the Free University, Department of Biological Psychology, Amsterdam.
Promotor: Prof. D.I. Boomsma
Co-promotors: Prof J.J. Hudziak, Dr. C.V. Dolan

1997-2001:
Bachelor and Master in Psychology at the University of Amsterdam, the Netherlands, with specializations in Statistical methods (cum laude) and neuroscience (cum laude)

WORK EXPERIENCE

January 2011 - present
Professor of Genetics in Psychiatry (0.88 fte, fixed term), Academic Medical Center, Amsterdam

November 2007 - December 2011
Senior Researcher (0.88 fte, tenure position), Department of Psychiatry, Utrecht Medical Center, Utrecht.
The main research projects in which I am involved are:
- “Improvement of phenotyping in Genome Wide Association studies on schizophrenia: an application of Latent Class Factor Analysis”. (funded by NWO; 250,000 Euro)
I am the prinicipal investigator of this project. The main goal of the current proposal is to improve the assessment of individual differences in schizophrenia, and to incorporate these improved phenotypic assessments in subsequent Genome Wide Association analyses.
- “Genetic Risk and Outcome in Psychosis (GROUP)”
This is a longitudinal study on gene-environment vulnerability and resilience in both clinical and non-clinical populations which offers the opportunity to elucidate etiological and pathogenetic factors influencing the onset and course of psychotic disorders.
- “The European First Episode Schizophrenia Trial (EUFEST)”
I am the statistical advisor of this project. The aim of the European First Episode Schizophrenia Trial (EUFEST) is to compare treatment with amisulpride, quetiapine, olanzapine and ziprasidone to a low dose of haloperidol in an unselected sample of first episode schizophrenia patients with minimal prior exposure to antipsychotics.
- “Optimization of Treatment and Management of Schizophrenia in Europe (OPTiMiSE; funded by FP7; 11,800,000 Euro). I am the senior statistical consultant of this project. The main aim of this study is to optimise current treatments in schizophrenia and explore novel therapeutic options for schizophrenia.

October 2010 - April 2011
Visiting scientist, Department of Genetic Epidemiology, Queensland Institute of Medical Research, Brisbane, Australia.
The aim of this visit was to collaborate with Prof. Dr. Peter Visscher and Dr. Naomi Wray on a study on the role of Copy Number Variants (CNVs) in mental retardation and schizophrenia. I discovered a novel region which is significantly enriched for large (>1Mb) CNVs in patients with mental retardation and schizophrenia compared to patients with mental retardation only. This work is not yet submitted for publication as the CNVs are currently verified based on PCR analysis but I expect that it will be submitted next month.

January 2007 - October 2007
Postdoc (0.8 fte, fixed term), Department of Biological Psychology, Vrije Universiteit, Amsterdam. This postdoc project was a continuation of the research project which started in September 2006.

October 2006-December 2006
Postdoc (1 fte, fixed term), Department of statistical genetics, Wellcome Trust Center of Human Genetics, Oxford, United Kingdom. In collaboration with Prof. dr. L.R. Cardon and Dr. D.M. Evans, two experts in statistical genetics, I worked on a statistical innovation in Genome Wide Association studies, and developed a method to increase statistical power to detect a functional genetic variant by prediction of unobserved SNPs based on information from the HapMap sample

September 2006-October 2006
Postdoc (0.8 fte, fixed term), Department of Biological Psychology, Vrije Universiteit, Amsterdam.
As part of this position, I collaborated with Prof. dr. M.C. Neale, and studied the psychometric
properties of a questionnaire that is used to assess smoking addiction: the Fagerström test for
nicotine dependence. This collaboration was continued in January, 2007.

September 2001-September 2006
AIO (0.8 fte, fixed term), Department of Biological Psychology, Vrije Universiteit, Amsterdam. The topic of the project was the exploration of genetic and environmental influences on Attention Problems and related childhood behavior problems, such as aggression and anxiety/depression.

GRANTS

2010 Netherlands Brain Foundation: On the role of copy number variants in autism: what about the other allele? PI Dr. J.A.S. Vorstman, 149,500 Euro. I am a co-investigator.
2009 FP7: Optimization of Treatment and Management of Schizophrenia in Europe (OPTiMiSE), PI Prof. R.S. Kahn, 11,800,000 Euro. I am the senior statistical advisor.
2008 Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). Innovational Research Incentives Scheme, VENI. 250,000 Euro.
2006 Rubicon grant from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO).16,000 Euro

TEACHING AND SUPERVISION

- Promotor of PhD student (expected end date October 2014). Title project "Methodological aspects of genetic association studies"
- Promotor of PhD student (expected end date July 2014). Title project "Longitudinal trajectories of symptom dimensions in adolescents with a family history of schizophrenia or bipolar disorder"
- Promotor of PhD student (expected end date December 2011). Title project "The influence of familial loading on clinical characteristics of patients with schizophrenia and their relatives"
- Initiation and organization of a weekly Statistical Methods workgroup in which I teach a wide variety of statistical methods to master students and PhD students
- Teaching in genetics and methodology (courses "Genes and Behavior", "Genetic Methodology", and the "Mx workshop"

SOFTWARE

- General Statistical software: SPSS, R
- Structural Equation Modeling software: Lisrel, Mplus, LatentGold, Mx
- Software for genetic analyses: Mx, Plink, Merlin, Beagle
- Program Languages: Fortran

 

 

RELATED PROFESSIONAL EXPERIENCE

- Initiator (in collaboration with Professor dr. Burbach) of a new research focus "Systems Neurobiology" which will be financed and implemented by the Division Brain, UMC Utrecht.
- Reviewer for "The Lancet", "Journal of the American Academy of Child and Adolescent Psychiatry", "Neuropsychiatric Genetics", BMC Psychiatry", "Psychiatry Research", "European Journal of Human Genetics", "Comprehensive Psychiatry", PlosOne", "Biological Psychology", and "Psychological Medicine".
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COLLABORATIONS

- Prof. dr. Peter M. Visscher and Dr. Naomi Wray at the Department of Genetic Epidemiology, Queensland Institute of Medical Research, Brisbane, Australia.
Website: http://genepi.qimr.edu.au/staff/?staffusername=peterV
- Prof. dr. Roel Ophoff at the UCLA Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, Los Angeles
- Prof. dr. Dorret Boomsma at the Department of Biological Psychology, Free University, Amsterdam, the Netherlands
- Dr. Denny Borsboom at the Department of Psychological Methods, Faculty of Social and Behavioural Sciences, University of Amsterdam, the Netherlands
http://home.medewerker.uva.nl/d.borsboom/
- Prof. dr. Jeroen Vermunt at the Department of Methodology and Statistics, Tilburg School of Social and Behavioral Sciences, the Netherlands
http://www.tilburguniversity.edu/webwijs/show/?uid=j.k.vermunt
- Prof. dr. Conor V. Dolan at the Department of Biological Psychology, Free University, Amsterdam, the Netherlands

SCIENTIFIC PUBLICATIONS

International (refereed) journals (journal impact factor)

- Derks EM et al. (in revision). The identification of family subtype based on the assessment of subclinical levels of psychosis in relatives.
- Derks EM et al. (in press). Investigation of the genetic association between quantitative measures of psychosis and schizophrenia: a polygenic risk score analysis. PlosOne.
- Derks EM et al (in press). Segment-wise genome-wide association analysis identifies a candidate region associated with schizophrenia in three independent samples. PlosOne.
- Kirstin Daalman, Kelly M.J. Diederen1, Eske M. Derks1, Remko van Lutterveld1, René S. Kahn1, Iris E.C. Sommer1. Childhood trauma and auditory verbal hallucinations (in press). Psychological Medicine.
- Kirstin Daalman1, Sanne Verkooijen1, Eske M Derks2, André Aleman3, Iris EC Sommer1. (in press). Schizophrenia Research.
- Derks EM, Collin G, van Haren NE, Schnack HG, Hulshoff Pol HE et al. (in press). Schizophr. Res.
- Fleischhacker WW, Derks E, Kahn RS. (in press). Schizophr. Res. 138:39-40
- Maat A., Fett, A, Derks E, GROUP (in press). Social cognition and quality of life in schizophrenia. Psychological Medicine.
- Sommer,I.E., Slotema,C.W., Daskalakis,Z.J., Derks,E.M., Blom,J.D. and van der,G.M. (in press). The Treatment of Hallucinations in Schizophrenia Spectrum Disorders. Schizophrenia Bulletin.
- Stringer,S., Wray,N.R., Kahn,R.S. and Derks,E.M., 2011. Underestimated effect sizes in GWAS: fundamental limitations of single SNP analysis for dichotomous phenotypes. PLoS One. 6, e27964.
- Landolt,K., Rossler,W., Burns,T., jdacic-Gross,V., Galderisi,S., Libiger,J., Naber,D., Derks,E.M., Kahn,R.S. and Fleischhacker,W.W., 2011a. The interrelation of needs and quality of life in first-episode schizophrenia. Eur Arch Psychiatry Clin Neurosci.
- Landolt,K., Rossler,W., Burns,T., jdacic-Gross,V., Galderisi,S., Libiger,J., Naber,D., Derks,E.M., Kahn,R.S. and Fleischhacker,W.W., 2011b. Unmet needs in patients with first-episode schizophrenia: a longitudinal perspective. Psychol Med. 1-13.
- Derks EM, Allardyce J, Boks MP, Vermunt JK, Hijman R, Ophoff RA, Genetic Risk and Outcome in Psychosis (GROUP) (in press). Kraepelin was right: A latent class analysis of symptom dimensions in patients and controls. Schizophrenia Bulletin (7.47)
- Visscher PM, Goddard ME, Derks EM, Wray NR (in press). Evidence based psychiatric genetics, AKA the false dichotomy between common and rare variant hypotheses. Molecular Psychiatry (15.05)
- Boos HB, Cahn W, van Haren NE, Derks EM, Brouwer RM, Schnack HG, Hulshoff Pol HE, Kahn RS (in press). Focal and global brain measurements in siblings of patients with schizophrenia. Schizophrenia Bulletin (7.47).
- Volavka J, Czobor P, Derks EM, Bitter I, Libiger J, Kahn RS, Fleischhacker WW for the EUFEST Study Group (in press). Efficacy of Antipsychotic Drugs against Hostility in the European First Episode Schizophrenia Trial (EUFEST). Journal of Clinical Psychiatry (5.22).
- Verweij KHW, Derks EM, Hendriks EJE, Kahn RS, Cahn W (in press). A short report on the collection of information through family history interviews. Twin Research and Human Genetics (2.10).
- Derks EM, Fleischhacker WW, Boter H, Peuskens J, Kahn RS for the EUFEST study group (2010). Antipsychotic drug treatment in first-episode psychosis: Should patients be switched to a different antipsychotic drug after two, four, or six weeks of non-response? Journal of Clinical Psychopharmacology, 30(2),176-180 (4.371)
- Gaebel W, Riesbeck M, von Wilmsdorff M, Burns T, Derks EM, Kahn RS, Rossler W, Fleischhacker WW, EUFEST Study Group (in press). Drug attitude as predictor for effectiveness in first-episode schizophrenia: results of an open randomized trial (EUFEST). European Neuropsychopharmacology (3.79).
- Boter H, Derks EM, Fleischhacker WW, Davidson M, Kahn RS (2010). Generalizability of the results of efficacy trials in first-episode schizophrenia: Comparisons between subgroups of participants of the European First Episode Schizophrenia Trial (EUFEST). Journal of Clinical Psychiatry, 71, 58-65. (5.22)
- Lubke GH, Hudziak JJ, Derks EM, van Bijsterveldt CEM, Boomsma DI (2009). Maternal ratings of attention problems and the relation to DSM-IV ADHD: Evidence for the existence of a continuum. Journal of the American Academy of Child and Adolescent Psychiatry, 48, 1085- 93.(4.845)
- Boks MP, Derks EM, Weisenberger DJ, Strengman E, Janson E, Sommer IE, Kahn RS, Ophoff RA (2009). The relationship of DNA methylation with age, gender and genotype in twins and healthy controls. Plos One, e6767.
- Derks EM, Verweij KH, Kahn RS. and Cahn W(2009). The calculation of familial loading in schizophrenia. Schizophrenia Research, 111, 198-199. (4.174)
- Van ’t Ent D., van Beijsterveldt,T.C., Derks EM, Hudziak,J.J., Veltman,D.J., Todd,R.D., Boomsma,D.I. and De Geus,E.J. (2009). Neuroimaging of response interference in twins concordant or discordant for inattention and hyperactivity symptoms. Neuroscience. (3.556)
- Poelen,E.A., Derks EM, Engels,R.C., van Leeuwe,J.F., Scholte,R.H., Willemsen,G. and Boomsma,D.I., 2008. The relative contribution of genes and environment to alcohol use in early adolescents: are similar factors related to initiation of alcohol use and frequency of drinking? Alcohol Clin Exp Res. 32, 975-982. (3.166)
- Derks EM, Hudziak JJ, Dolan CV, Van Beijsterveldt CEM, Verhulst FC, Boomsma DI (2008). Genetic and environmental influences on the relation between Attention Problems and Attention Deficit Hyperactivity disorder. Behavior Genetics, 38, 11-23. (3.289)
- Derks EM, Hudziak JJ , Dolan CV, van Beijsterveldt CEM, Verhulst FC, Boomsma DI (2007). Why More Boys Than Girls With ADHD Receive Treatment: A Study of Dutch Twins. Twin Research and Human Genetics, 10,765-770. (2.097)
- Derks EM, Lehn H, Hudziak, JJ, Heutink P, van Beijsterveldt CEM, Boomsma DI (2007). Attention problems and attention deficit hyperactivity disorder in discordant and concordant MZ twins: Evidence of environmental mediators. Journal of the American Academy of Child and Adolescent Psychiatry,46(1), 83-91 (4.845)
- Derks EM, Dolan CV, Hudziak JJ, Neale MC & Boomsma DI (2007). Assessment and etiology of attention deficit hyperactivity disorder and oppositional defiant disorder in boys and girls. Behavior Genetics, 37, 559-566. (3.289)
- Bartels, M., van Beijsterveldt, C. E. M., Derks, E. M., Stroet, T. M., Polderman, T. J. C., Hudziak, J. J., & Boomsma, D. I. (2007). Young Netherlands Twin Register (Y-NTR): A longitudinal multiple informant study of problem behavior. Twin Research and Human Genetics, 10, 3-11. (2.097)
- Ent DV, Lehn H, Derks EM, Hudziak JJ, Van Strien NM, Veltman DJ, De Geus EJC, Todd RD, & Boomsma DI (2007). A structural MRI study in monozygotic twins concordant or discordant for attention/hyperactivity problems: Evidence for genetic and environmental heterogeneity in the developing brain. Neuroimage, 35, 1004-1020. (5.694)
- Polderman TJC, Derks EM, Hudziak JJ, Verhulst FC, Posthuma D & Boomsma DI (2007). Across the continuum of Attention Skills: A twin study of the SWAN ADHD rating scale. Journal of Child Psychology and Psychiatry, 48, 1080-1087. (4.854)
- Derks EM, Dolan, CV, and Boomsma, DI (2006). A test of the Equal Environment Assumption (EEA) in multivariate twin studies. Twin Research and Human Genetics, 9, 403-411. (2.097)
- Derks EM, Dolan CV, and Boomsma DI (2006). Statistical power to detect genetic and environmental influences in the presence of data missing at random. Twin Research and Human Genetics, 10,159-167. (2.097)
- Derks EM, Hudziak JJ, Van Beijsterveldt CEM, Dolan CV, and Boomsma DI. Genetic analyses of maternal and teacher ratings on Attention Problems in seven-year-old Dutch twins (2006). Behavior Genetics, 36, 833-844. (3.289)
- Derks EM, Hudziak JJ, Dolan CV, Ferdinand RF and Boomsma DI (2006). The relations between DISC-IV DSM diagnoses of ADHD and multi-informant CBCL-AP syndrome scores. Comprehensive Psychiatry, 47, 116-122. (2.054)
- Althoff RR, Copeland WE, Stanger C, Derks EM, Todd RD, Neuman RJ, Boomsma DI, and Hudziak JJ (2006). The Latent Class Structure of ADHD is Stable Across Informants. Twin Research and Human Genetics, 9, 507-522. (2.097)
- Boomsma DI, Rebollo I, Derks EM, Beijsterveldt CEM van, Althoff RR, Rettew DC and Hudziak JJ (2006). Longitudinal Stability of the CBCL-Juvenile Bipolar Disorder Phenotype: A Study in Dutch Twins. Biological Psychiatry, 60, 912- 920. (8.672)
- Hudziak JJ, Althoff RR, Derks EM, Faraone SV and Boomsma DI. Prevalence and genetic architecture of child behavior checklist-juvenile bipolar disorder (2005). Biological Psychiatry, 58, 562-568. (8.672)
- Hudziak JJ, Derks EM, Althoff RR, Rettew DC and Boomsma DI (2005). The genetic and environmental contributions to attention deficit hyperactivity disorder as measured by the Conners' Rating Scales - Revised. American Journal of Psychiatry, 162, 1614-1620. (10.545)
- Hudziak JJ, Derks EM, Althoff RR, Copeland WM and Boomsma DI (2005). The genetic and environmental contributions to oppositional defiant behavior: A multi-informant twin study. Journal of the American Academy of Child and Adolescent Psychiatry, 44, 907-914. (4.845)
- Derks EM, Dolan CV, and Boomsma DI (2004). Effects of censoring on parameter estimates and power in genetic modeling. Twin Research, 7, 659-669. (2.097)
- Derks EM, Hudziak JJ, Van Beijsterveldt CEM, Dolan CV and Boomsma DI (2004). A study of genetic and environmental influences on maternal and paternal CBCL syndrome scores in a large sample of 3-year-old Dutch twins. Behavior Genetics, 34, 571-583. (3.289)
- Hudziak JJ, Beijsterveldt van CEM, Bartels M, Rietveld MJH, Rettew DC, Derks EM and Boomsma DI (2003). Individual differences in aggression: genetic analyses by age, gender, and informant in 3-, 7-, and 10-year-old Dutch twins. Behavior Genetics, 33, 575-589. (3.289)
- Boomsma DI, Vink JM, van Beijsterveldt CEM, Geus EJC, Beem AL, Mulder EJCM, Derks EM, Riese H, Willemsen AHM, Bartels M, van den Berg M, Kupper HM, Polderman JC, Posthuma D, Rietveld MJH, Stubbe JH, Knol LI, Stroet T and van Baal GCM (2002). Netherlands Twin Register: a focus on longitudinal research. Twin Research, 5, 1-6. (2.097)

Selection of conference/Meeting contributions and lectures

- Invited oral presentation: “Segment-wise genome wide association analysis identifies a limited number of replicable candidate regions associated with schizophrenia”. October 6th 2010, World Congress of Psychiatric Genetics, 2010.
- Oral presentation: “Improvement of phenotyping in Genome Wide Association studies on schizophrenia: an application of latent class factor analysis”. November 7th, 2009, World Congress of Psychiatric Genetics, 2009
- Invited lecture: “A Finite Mixture Regression Model for Testing Association at Hidden Loci in Genome-wide Quantitative Trait Association Analysis”. Workshop Genetic Data Analysis, October 2nd , 2007, Amsterdam, the Netherlands.
- Oral presentation: “Monozygotic Twins Discordant for Attention Problems and Attention- Deficit/Hyperactivity Disorder”. Symposium “Attention Problems and ADHD”, April 4th 2006, Vrije Universiteit, Amsterdam, the Netherlands.
- Oral presentation: “Searching for genes related to ADHD: refining the phenotype”. The Dutch Endo-Neuro-Psycho meeting, June 2nd 2005, Doorwerth, the Netherlands.
- Oral presentation: “Genetic analyses of teacher ratings on aggression, attention, and anxiety in 7, 10, and 12-year old children”. The 34th Behavior Genetics Association Annual Meeting, June 28th, 2004, Aix-en-Provence, France.

 

 

Prof. MD PhD W. van den Brink (Addiction: pathogenesis, mechanisms of relapse and treatment effectiveness)

Prof. PhD E.M. Derks (Genetics in Psychiatry)

Overall aim of research
Individual differences exist in the risk to develop psychiatric disorders. I aim to understand which factors contribute to these individual differences; why is it that some people are psychiatrically much more vulnerable than others? We have moved beyond the nature-nurture debate, as it is now clear that both genetic and environmental factors contribute. However, we have not yet revealed the specific etiological pathways which lead to psychiatric disorders. The identification of genetic and environmental risk factors requires thorough investigation of clinical symptoms, neurobiological functioning, structural and functional brain assessments, and molecular biology. I aim to integrate research findings obtained at these different levels of complexity. My position at a department of psychiatry allows me to collaborate with psychiatrists and neuroscientists and to conduct interdisciplinary research that is needed to increase the understanding of highly complex, multifactorial disorders.

Research at UMCU (2007-2011)
At UMCU, my research was primarily supported by a VENI grant. The overall aim of this project was to investigate how phenotypic heterogeneity can be accounted for in gene finding studies. This has resulted in important findings; showing that disorganization symptoms in schizophrenia patients are most strongly associated with genetic variants and with progressive changes in brain volume provided important directions for future studies (Derks et al. 2012d; Derks et al. 2012a). Second, I have developed new statistical methods for detecting genetic variants. For example, genetic analyses which focus on chromosomal segments were shown to have increased statistical power compared to analyses which focus on the role of individual Single Nucleotide Polymorphisms (Derks et al. 2012e). In total, the Veni project has resulted in 19 publications (8 first author, 2 last author, 9 co-author).

Research at AMC (2012-present)
In January 2012, I moved to the Academic Medical Center Amsterdam where I became professor of Genetics in Psychiatry. The main aim of my research group is to investigate the role of genetic factors in psychiatric conditions, including addiction, anxiety disorders, compulsive disorders, and schizophrenia. The focus of my research is on the development of new statistical methods aimed at discovering associations between genetic variants and psychiatric conditions. The ultimate goal is to study the biological processes which result in a psychiatric condition, starting with the genetic mutation with psychiatric diagnosis as the endpoint.
 

Postdocs
MD PhD F.J. Vorspan

PhD Students
M. Vleeschouwer