Disturbances of the cell at low doses

Blood samples have been irradiated at 6 radiation doses ranging from 5 and 500 mGy in order to study the impact of gamma radiation on T CD4 genes of humane lymphocytes. These lymphocytes are key players of the immune response. The results show that among the 17000 genes that are effectively expressed in the cells in question, 2745 have an expression modulated by the irradiation. Among these genes the statistic analysis puts aside 370 genes that can be parted into 2 groups: a group of 68 genes for which their expression increases with the radiation doses and a group of 302 genes for which their expression increases significantly as soon as 5 mGy and stays at that level whatever the radiation dose. This fact is new and shows a disturbance at the scale of the cell even at very low doses. (A.C.)