Subject No. Age Sex Frag- ments Dicentrics Rings Exch- anges. No. of Chromosome Aberrations No. of Cells with Aberrations Chromatid Breaks Isogaps Remarks* Exposed, 70 rad (continued) 70 25 -F 81 18 F 84 9 M 1 1 2 1 1 1 1 2 2 2 2 Exposed in utero Child of exposed OF I Unexposed 105 5 F 1 830 25 M 1 859 71 ~=O#F 1 1 1 931 10 M 1 1 1 938 25 *F l 1 1 982 43 F 1005 31 M 3 1043 29 =F 3 3 1 1 1 3 1 2 2 * Except for Subject Nos. 3 and 64, all thyroid pathology was adenomatous goiter. Case 64 had a mixed papillary and follicular carcinoma of the thyroid. aa 3 Case 3 is a hypothyroid child. ee et ee ee ee