Association between AGTR1 gene polymorphism and risk of nonalcoholic fatty liver disease

Objective To investigate the association between type 1 angiotensin II receptor( AGTR1) rs3772622 polymorphism and nonalcoholic fatty liver disease( NAFLD) and the interaction between the locus and patatin- like phospholipase domain- containing protein 3( PNPLA3) rs738409 polymorphism. Methods A total of 241 patients who were diagnosed with NAFLD by B- mode ultrasound in Qingdao Municipal Hospital from September 2013 to September 2014 and 205 healthy controls were included. AGTR1 rs3772622 and PNPLA3rs738409 were determined by polymerase chain reaction and a genotyping method. A statistical analysis was performed on allele frequency,genotype frequency,and clinical / biochemical data of the two loci. According to different data types,t test and Pearson chi- square test were separately performed. The variant genotypes of AGTR1 rs3772622 and PNPLA3 rs738409 for risk of NAFLD were analyzed by Logistic regression analysis. The interactions between AGTR1 rs3772622 and PNPLA3 rs738409 were investigated by generalized multifactor dimensionality reduction. Results No significant differences were found between the NAFLD group and the control group as regards to the distribution of genotypes and alleles of AGTR1 rs3772622( P > 0. 05). Compared with the wild type,the AGTR1 rs3772622 variant did not significantly increase the risk of NAFLD( P > 0. 05) and the variant carriers of PNPLA3 rs738409 had a 2. 09- fold increase in the risk of NAFLD [odds ratio( OR) = 2. 09,95% confidence interval( CI) : 1. 35- 3. 23,P = 0. 001]. The combination of AGTR1 rs3772622 and PNPLA3rs738409 significantly increased the risk of NAFLD( OR = 3. 60,95% CI: 1. 50- 6. 23,P < 0. 001). There were significant differences in alanine aminotransferase and aspartate aminotransferase between the single variant carriers of PNPLA3 rs738409 and the carriers of the two variants( both P < 0. 05). Conclusion The polymorphism of AGTR1 rs3772622 is not associated with the development and progression of NAFLD in Chinese population,but the AGTR1 rs3772622 variant can increase the risk of NAFLD in variant carriers of PNPLA3 rs738409.