English abstract
Background: Non alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide characterized by increased lipid content in hepatocytes. NAFLD is a spectrum of liver diseases that range from simple steatosis to non-alcoholic steatohepatitis (NASH) to liver cirrhosis and hepatocellular. Several genes are found to be associated with NAFLD. Recently, multiple genome wide association studies have implicated a strong role of variation in the PNPLA3 gene to the etiology of NAFLD, its association with the metabolic syndrome and progression of NAFLD. Therefore this study aimed to study the heritability of Fatty liver risk in Omani population using multigeneration family model and study the role of PNPLA3 1148M variant (rs738409) in the heritability of traits defining fatty liver.
Methods: A total of 1225 individuals of Arab ancestry were chosen from the Oman Family Study in Nizwa region. A predesigned TaqMan probe was purchased for genotyping of rs738409 using real-time PCR. Several programs (R-packages, Pedstat, SOLAR, SPSS) were used to run the proper statistical analysis.
Results: The minor G allele frequency that codes for methionine position 148 is common in the study population accounting for 26%. Male subjects showed a significant difference in the mean of 2hr-sugar and the plasma TG among the three genotype groups. Approximately, twenty one percent of total phenotypic variation in fatty liver probability is explained by genetic factors with very significant P-value.
Conclusion: The study showed no significant association between the 1148M variant with fatty liver predicted by fatty liver index. A positive association was observed between the variant and traits defining type 2 diabetes. Future functional work is required to investigate the role of adiponutrin in regulation of blood glucose levels
