Abstract: Objective To study the transforming growth factor α（TGF-α）-435G/A gene polymorphism in patients with nonalcoholic fatty liver diseases（NAFLD）. Methods 126 patients with NAFLD between February 2013 and February 2015 were recruited in our hospital,and 121 healthy individuals were also included at the same time as control. The polymorphism of TGF-α -435G/A gene in peripheral blood was analyzed by restriction fragment length polymorphism （RFLP） and the data obtained were processed by SPSS software. Results There was no significant difference neither in the TGFα -435G/A genotypes nor the distribution of TGFα-435G/A allele between patients with NAFLD and control（P>0.05）,however,there were significant differences in AA and GG genotype frequency （39.2% vs. 25.7%,and 16.3% vs. 35.3%） and their allele frequency （61.4% vs. 45.2%,and 38.6% vs. 54.8%） between the two groups （x²=15.43,P<0.05;x²=16.32,P<0.05）;And further study showed that patients with NAFLD with different steatosis had different AA GG,AG genotype frequencies and their allele frequencies with relatively high percentage of homozygote（AA,GG） in patients with severe fatty liver diseases. Conclusions There is a certain correlation between the gene mutation of TGFα-435G/A and the incidence of NAFLD,and the frequency of different genotypes and allele might be related to the severity of NAFLD.

Key words: Nonalcoholic fatty liver disease, Transforming growth factor α, Gene polymorphism, Genotype, Allele