DCX and hypothyroidism: Our data show that developmental iodine-deficiency and hypothyroidism cause irreversible mal-regulation of doublecortin and NCAM-180 a few weeks before the obvious injury of nerve fibers in the hippocampus, implying that developmental iodine deficiency and hypothyroidism may impair the expression of doublecortin and NCAM-180, leading to disfunction of nerve fibers and hippocampal development.