The genes transcriptionally activated by the XBP1, ATF6 or ATF4 displayed a similar trend in IUGR liver samples, reaching statistical significance in the case of GRP78/BiP (2.3 ± 2.0 vs 1 ± 0.46; p<0.05) (Fig 1C). The gene discussed is XBP1; the disease is fetal growth restriction.