A large-scale gene expression database on the effect of low doses of radiation: A systems biology approach

Current radiation protection regulatory limits are based on the linear non-threshold theory using health data from atomic bombing survivors. Studies in recent years sparked debate on the validity of the theory, especially at low doses. Recent advances in molecular biology have shown that different genes are triggered by low doses versus high doses of ionising radiation. Identifying genes involved in the response to low doses is therefore critical for a better prediction of a possible clinical outcome following radiation exposure. The increasing interest in the effect of low doses of radiation coincides with the breakthrough in the development of new high-throughput technologies in molecular biology. Microarrays constitute a good example, allowing simultaneous measurement of the expression of thousands of genes. Applying a systems biology approach on these data will shed light on the relationship between gene expression and different parameters like dose, tissue and organism. Additionally, identification of pathways triggered upon low doses of radiation might open new opportunities towards biodosimetry and appropriate regulation.