INHERITANCE OF DEFECTIVE ORGANIFICATION OF IODINE IN FAMILIAL GOITROUS CRETINISM*

Abstract

Defective organification of iodine was studied in goitrous cretins and their siblings. The genealogy is presented of 90 members of four generations of two related sibships in which 7 of 11 children in one sibship and 2 of 7 children in the other sibship were cretins. Rapid thyroidal uptake and release of I131, prompt and marked discharge of I131 after administration of KSCN, and the chromatographic finding of iodide alone in serum and urine up to forty-eight hours after administration of 400 μc. of I131 constituted evidence for a defect in thyroidal organification of iodine in these cretins. Five apparently normal siblings and 8 other relatives studied failed to show any evidence of this defect. Apparently the only mechanism of inheritance that could explain the pattern of this abnormality involves a gene that is completely recessive—at least by present methods of testing.