It is the last result that is of the greatest concern, because cell division results in increasing the population of new cells. mutation occures in somatic outcomes: If the (body) cells, there are three possible Mutation in the somatic cells of embryos may lead to embryo death ( spontaneous abortion or miscarriage), or embryopathy (abnormal development), whereas mutations in adult tissues are believed to result in malignacies and are possibly involved in the acing process. Finally, mutations in gametic cells can lead to ab- normal gametes (eggs or sperm cells) or sterility, both of which are forms of reproductive toxicity. If the mutant gametes are viable, the subsequent fertilization can result in embryo death, embryopathy, or some hereditary effects. The Loma Linda Proposal presents suggested evidence of radiationrelated effects in the Marshallese. posal, As seen in Table 4 of the Pro- of the 17 leading causes of death in the Marshall Islands, 1974 to 1976, cancer is tied with cerebrovascular diseases as the leading cause of death. Prematurity (a form of embryopathy) next and third leading cause of death. is the In addition concgential defects accounted for 3.3% of all deaths, indicating the substantial severity of these defects. At present, the greatest need is both for studies involving large scale genetic analyses of the Marshallese and for more diversified, specific studies of those exposed. Results from both of these efforts would contribute significantly to the interpretation of and correlation with isolated findings. Presently, genetic screeing techniques should be regarded as the best instrument for detecting genetic injury at a stage when corrective action can be taken for the benefit of affected individuals.