An animal study had shown that hypothyroidism decreased the expression of HO-1, GRP78 and C/EBP homologous protein (CHOP) genes/proteins in the mid-gestation while increased the expression of HIF-1α, CHOP and nuclear factor erythroid 2-related factor 2 (NRF2) genes/proteins (15). This evidence concerns the gene DDIT3 and hypothyroidism.