SP 9

Functional Validation I: Gene and molecular analysis

In our most recent genome wide association study for alcohol dependence (GWAS) 13 single nucleotide polymorphisms (SNPs) have been identified as top markers associated with alcoholism (Frank et al., 2012). Further candidate genes will be identified through our “genetic pipeline” (SP2, 3) during the course of the e:Med program. Whether those gene variants are causally linked to alcohol-related behaviors and how the function of the genes associated with these variants contribute to alcoholism is not clear. Only appropriate animal models allow the functional validation of those putative candidate genes. We propose to use (i) Drosophila as a genetic model system with its short generation time and broad set of genetic tools to analyze the function of orthologues candidate genes in alcohol-induced behaviors. In addition, we will use (ii) humanized mouse models that carry the human SNP of interest as these are powerful functional validation tools and can provide a deeper mechanistical insight into the pathogenic nature of the gene variant of interest. In flies and mice alcohol-induced behaviors are phenotypically and mechanistically similar to those observed in humans. In addition, we have previously identified in flies a cellular neuronal stress pathway required for alcohol-induced behaviors that might be conserved in humans. Our goal is to generate appropriate Drosophila mutants for our top candidate genes and analyze the consequences of those candidate gene functions in alcohol sensitivity, tolerance, preference, consumption, and finally examine their relationship to the previously discovered cellular stress pathway with neuroanatomical and molecular-genetic approaches. The generated humanized mouse models will be studied in-depth in SP5 for addictive behavior; i.e., alcohol-seeking and relapse and pharmaco response to anti-relapse compounds as well.

Keywords: validation of candidate genes cellular stress response