Human health conditions are largely determined by a complex interplay among genetic susceptibility, environmental factors, and aging. The RadGenomics project, which began in April 2001, promotes analysis of genes in response to irradiation, identification of their allelic variants in the human population, development of an effective procedure for quantitating individual radio-sensitivity, and analysis of the interrelationship between genetic heterogeneity and susceptibility to irradiation. Major groups of genes with which the project will concern itself include DNA repair genes, cell cycle genes, oncogenes, tumor suppressor genes, genes for programmed cell death, genes for signal transduction, and genes for oxidative processes. The outcome of the RadGenomics project should lead to improved protocols for personalized radiotherapy and reduce the possible side effects of treatment. The project will contribute to future research on the molecular mechanisms of radiation sensitivity in humans and stimulate the development of new high-throughput technology for a broader application of the biological and medical sciences. Identification of functionally important polymorphisms in the radiation response genes may determine individual differences in sensitivity to radiation exposure. The staff members, who are specialists in a variety of fields including genome science, radiation biology, medical science, molecular biology, and bioinformatics, have come to the RadGenomics project from various universities, companies, and research institutes.