Genetic and environmental susceptibility to non-alcoholic fatty liver disease.

While the majority of those with non-alcoholic fatty liver disease (NAFLD) will have simple hepatic steatosis, a minority will develop progressive steatohepatitis. Family studies and inter-ethnic variations in susceptibility suggest that genetic factors may be important in determining disease risk. Although no genetic associations with advanced NAFLD have been replicated in large studies, preliminary data suggest that polymorphisms in genes controlling lipid metabolism, pro-inflammatory cytokines, fibrotic mediators and oxidative stress may be associated with steatohepatitis and/or fibrosis. Recent whole genome-wide scans have identified genes contributing to inherited susceptibility to steatosis and it seems likely that similar approaches will identify genes associated with disease progression in the near future.