Background and aim: The aim of this study was to investigate the influence of polygenetic polymorphisms, which play a role in the pathogenesis of metabolic syndrome, on the susceptibility to non-alcoholic fatty liver disease (NAFLD) of Chinese people.
Methods: The subjects were selected from an epidemiological survey in the Guangdong province of southern China. In each polymorphism study, 50-117 subjects who met the diagnostic criteria of NAFLD and had typical clinical and ultrasonographic findings were placed into the case group. Using a nested case-control design, the same numbers of matched people without NAFLD were included as controls. Single nucleotide polymorphisms (SNP) at nine positions in seven candidate genes were tested. These SNP were found to be associated with the pathogenesis of metabolic syndrome. Genetic analyses were performed using genomic DNA extracted from peripheral blood leukocytes. Polymerase chain reaction-restriction fragment length polymorphism was applied to detect SNP.
Results: Most candidate genes' SNP were associated with susceptibility to NAFLD. Some showed positive relationships (increased risk): tumor necrosis factor-alpha-238, adiponectin-45, leptin-2548, peroxisome proliferator-activated receptors-161 and phosphatidyletha-nolamine N-methyltransferase-175. Other SNP demonstrated a negative association (decreased risk): adiponectin-276 and hepatic lipase-514. Only two were not associated: tumor necrosis factor-alpha-380 and peroxisome proliferator-activated receptors-gamma co-activator-1alpha-482.
Conclusion: Most candidate genes' SNP examined in metabolic syndrome patients were associated with susceptibility to NAFLD.