Liver tissue H&E staining also verified that OVX increased fat deposition in the liver and caused hepatic steatosis in female mice (Figure 2E), while FGF21 LKO failed to reverse (p > 0.05) the OVX-induced liver weight gain and hepatic steatosis in OVX mice (Figure 2C–E). The gene discussed is FGF21; the disease is fatty liver disease.