Differential gene expression in the forebrain of the GD20 fetus. All PTU doses represent the maternal dose administered. A, The gene Camk4 was downregulated in response to 2 and 3 ppm PTU. B, Thyroid receptor beta (Thrb) was the only other differentially expressed gene in the GD20 fetus, and a significant change was only observed in the 3 ppm PTU dose group. An n 1/4 6–9 was analyzed per treatment; significant downregulation of both genes was determined by an overall ANOVA, a1/4 0.01. All asterisks represent significant dose effects as determined by mean contrast tests, a1/4 0.05. All error bars represent 6 SEM.