Background/purpose: The aim of this study was to determine the association of single nucleotide polymorphism (SNP) in patatin-like phospholipase domain-containing 3 (PNPLA3) at I148 with histological severity of non-alcoholic fatty liver disease (NAFLD).
Methods: Patients were selected for the study if they had histological evidence of NAFLD and clinical evidence of non-alcoholic steatohepatits (NASH) cirrhosis. We included 50 NASH cirrhosis, 99 patients of NAFLD including 36 non-NASH fatty liver (NNFL) along with 63 NASH and 75 healthy controls. PNPLA3 genotyping was done by real-time PCR using a Taqman assay for rs738409.
Results: CC, CG, and GG frequencies were 45 (60.0%)/27 (36.0%)/3 (4.0%) in healthy control, 19 (52.8%)/14 (38.9%)/ 3 (8.3%) in NNFL, 18 (28.6%)/29 (46.0%)/16 (25.4%) in NASH, and 7 (14.6%), 25 (52.1%), 16 (33.3%) in cirrhosis. The frequency of G allele was significantly higher (62.6%) in NAFLD than in healthy control. The GG genotype had 20.25 times odds of NAFLD. The GG genotype had 6.53 times odds of having NASH. HOMA-IR > 1.6 had 3.81 times odds of having NASH. Regression analysis revealed that G allele odds of having cirrhosis was 3.9 times compared to C. The G allele was also significantly associated with steatosis, lobular inflammation, NAFLD activity score, and fibrosis.
Conclusion: PNPLA3 genotype showed an association with NAFLD, NASH, fibrosis, and cirrhosis.
Keywords: Non-alcoholic fatty liver disease; Nonalcoholic steatohepatitis; Patatin-like phospholipase domain-containing 3 gene; Single nucleotide polymorphism; rs738409.