Nevertheless, a clinical trial in NAFLD and NASH patients analysing electron microscopy of hepatocytes, demonstrated that significant mitochondrial abnormalities were present in patients with NASH, but not in those with hepatic steatosis, thus suggesting that peripheral insulin resistance could lead only to the development of fatty liver disease, not to inflammation as seen in steatohepatitis (Sanyal et al., 2001). The gene discussed is INS; the disease is fatty liver disease.