XBP1 and Hypocholesterolemia: Consistent with previous reports27,28, the AlbCre;Xbp1flx/flx mice displayed hypocholesterolemia and hypotriglyceridemia in the plasma without any significant liver histological, functional or gross phenotypic abnormalities throughout the first 15 weeks of life (Fig. 1a–c), suggesting that liver-specific ablation of Xbp1 did not noticeably affect fetal growth or liver development.