**7. Evidence for a gene-diet interaction**

Evidence suggests that variation in the genes for apolipoproteins A-I, A-IV, B, and E may contribute to the heterogeneity in the lipid response to dietary intervention. Many studies were unable to show significantly different responses between these genotype groups, and the genotypes showing the greatest response are not necessarily consistent between studies. There was insufficient evidence to assess whether lipid responsiveness is affected by variation in the genes for Apo C-III, lipoprotein lipase, hepatic lipase, the cholesteryl ester transfer protein. Although each of these gene products is essential in lipid metabolism, only a handful of studies have investigated variation in these genes, and most of these studies were unable to show significant gene-diet interactions (Masson et al, 2003).
