SMAD7 and vitamin A deficiency: The consumption of atRA, as the only source of dietary vitamin A, resulted in mRNA levels of Hfe2, Bmp6, and Smad7 be similar to those values obtained in the control group; however, the atRA diet failed to reverse the inhibitory effect of vitamin A deficiency on Hamp mRNA levels (2.8-fold, p = 0.002) in the liver.