Complete histopathologic examination of one group of mutant and MCAD+/+ control mice after a 24-h fast demonstrated diffuse microvesicular and macrovesicular hepatic steatosis in 6–8-wk-old MCAD−/− mice whereas MCAD+/+ mice had no histologic changes (Figure 5A and 5B). This evidence concerns the gene ACADM and Hepatic steatosis.