OBJECTIVETo study the relationship between COX-2 gene and hereditariness to Nonalcoholic fatty liver disease by detecting single nucleotide polymorphisms in the promoter of COX-2 gene.

METHODSGenotypes of 200 case patients with NAFLD and 206 control subjects were examined by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP). The DNA samples were extracted from the peripheral blood of all subjects.

RESULTSTwo SNPs, -1195G more than A and -765 G more than C, were identified with frequencies of variant alleles 54% and 5% in patients with NAFLD and 48% and 2% in control, respectively. A case-control analysis revealed a 1.13-fold (95% CI = 1.01-2.46) and a 2.35-fold (95% CI = 1.17-3.65) excess risk of developing NAFLD for -1195AA or -765CG genotype carriers compared with noncarriers. Compared with G-1195-G-765 containing haplotype, a greater risk of developing NAFLD was observed for A-1195-G-765 (OR =1.42; 95% CI =1.11-1.63) and A-1195-C-765 (OR = 4.24; 95% CI =1.72-14.22) containing haplotypes. A greater risk of developing NAFLD was observed for A-1195 and C-765 containing haplotype compared with other haplotype, suggesting an interaction between the -1195A and -765C in the context of haplotype.

CONCLUSIONSThese findings suggest that genetic variants in the COX-2 promoter may play an important role in mediating susceptibility to developing NAFLD in a Chinese population. -1195G more than A and -765G more than C in promoter region of Cyclooxygenase-2 gene, whose single nucleotide polymorphisms are related with development of NAFLD, are the significance factors of the susceptibility of NAFLD.