We aimed to better understand the genetics of gene expression over large distances and over time. In a first project, we performed a cross-sectional eQTL study in LCLs. The large statistical power provided by the large sample size allowed us to detect a large number of genes affected by eQTLs (in cis and in trans). Importantly, we provided biological explanations for several trans-eQTLs by showing that they first affected a gene in cis, which led to an effect on gene expression in trans. In a second project, we explored time-related changes in the genetic effects on gene expression. Our results suggest a model where ageing is associated to a loss of genetic control and to the downregulation of genes involved in protein synthesis and oxidative phosphorylation. The downregulation of these genes then appears to lead to the upregulation of genes involved in the lysosome, spliceosome and in the cytoskeleton.