To further analyze the cause of liver steatosis, we extracted liver tissue mRNA and performed a quantitative PCR analysis, which showed that the expressions of fatty acid uptake genes Cd36 and Fatp2, as well as that of Pparγ were significantly downregulated in the KO group, whereas the expression of Fatp4 and Fatp5 remained unchanged (Fig. 3A). The gene discussed is SLC27A4; the disease is fatty liver disease.