The laboratory for Cell Genetics (Cytogenetics) studies variation in genotype and phenotype, cell division pathways, cell death and genetic changes relevant for the increase of cancer in human. Genotoxicity tests assess the induction of DNA damage, gene mutations, structural and numerical chromosome aberrations. Their predictivity for cancer induction is supported by international studies relating mutations and activation of cancer related genes, and the induction of chromosome aberrations in lymphocytes with increased frequency of cancer. The genotoxicity tests and genotyping performed in the laboratory are used to study the mechanisms of action of mutagens/carcinogens (e.g. indirect mechanisms of genotoxicity by interference with spindle proteins, DNA repair enzymes and cellular trafficking), on development of predictive human genetic susceptibility biomarkers by combining genotyping and integrated phenotyping, on the assessment of potentially more susceptible sub-groups (e.g. stem cells and children) and on the risk of occupational/environmental exposure to newly developed material (e.g. nanotoxicology) Our strategy is a stepwise approach, from fundamental to applied research (including validation), at cellular/molecular level combining cytology with molecular approaches within interlaboratory and international collaborations. In the Developmental and Stem Cell Biology group, we are focusing on: * The role of the Wnt signaling in development and homeostasis by using transgenic mice and gene expression studies * Modeling the embryonic development by differentiating in vitro embryonic stem cell into muscle or neurons * Identifying the signaling pathways involved in some cancers involving the unregulated growth of stem cell, in particular in neural tissue. * Identifying by conserved genomics conserved regulatory elements implicated in limb development In the insect physiology group we concentrate on environmental biology, (eco)toxicology en risk assessment for the use of pesticides en other environment-related compounds, we use the bumble bee Bombus terrestris , which is of major economic and ecologic importance.