Name:
Dr. E.M. (Eske) Derks
Department of Psychiatry
Section Brain changes in developmental disorders
Function:
Assistant Professor
E-mail:
e.m.derks@umcutrecht.nl Tel: +31 88-7556034
Research group:
Prof Kahn, dr. Cahn, collaboration with Dr. Ophoff.
Title research line:
Improvement of phenotyping in Genome Wide Association studies on schizophrenia: an Application of Latent Class Factor Analysis
Summary research:
Schizophrenia is a highly heterogeneous disorder with a lifetime prevalence of 0.7%, and a heritability of 81%. Genome Wide Association (GWA) studies have the goal of unravelling the genetics of this complex disorder. However, the enormous investments that are made on the genotypic level (i.e. genotyping ~500,000 SNPs) are not matched by similar investments on the phenotypic level. As it is generally acknowledged that schizophrenia is a heterogeneous disorder and that symptom profiles vary between patients, it is likely that different clusters of symptoms are (partly) influenced by different genes. Collapsing patients with different genetic vulnerabilities into one single group may dramatically decrease the statistical power to detect a gene.
The main goal of my research is to improve the assessment of individual differences in schizophrenia, and to incorporate these improved phenotypic asssessments in subsequent GWA analyses. Based on latent class factor analyses (LCFA), we will identify factors that explain (co)variation in schizophrenia symptoms. The main advantage of this approach is the identification of unidimensional factors which will be more directly linked to genetic effects. The GWA study will be performed in a Dutch sample of 864 patients and 831 controls, and significant associations will be replicated in a sample of 1440 patients and 1469 controls.
Publications:
Derks EM, Dolan CV, Boomsma DI: A test of the equal environment assumption (EEA) in multivariate twin studies. Twin Res Hum Genet 2006; 9(3):403-411
Derks EM, Dolan CV, Boomsma DI: Statistical power to detect genetic and environmental influences in the presence of data missing at random. Twin Res Hum Genet 2007; 10(1):159-167
Derks EM, Dolan CV, Hudziak JJ, Neale MC, Boomsma DI: Assessment and etiology of attention deficit hyperactivity disorder and oppositional defiant disorder in boys and girls. Behav Genet 2007; 37(4):559-566
Derks EM, Hudziak JJ, Dolan CV, van Beijsterveldt TC, Verhulst FC, Boomsma DI: Genetic and environmental influences on the relation between attention problems and attention deficit hyperactivity disorder. Behav Genet 2008; 38(1):11-23
Derks EM, Verweij KH, Kahn RS, Cahn WC: The calculation of familial loading in schizophrenia. Schizophr Res 2009;