转化生长因子β1启动子区C-509T位点基因多态性与肝纤维化关系

Polymorphism of C-509T at promoter region of transforming growth factor β1 gene might be related to liver fibrosis

目的:建立多聚酶链式反应-限制性片段长度多态分析(PCR-RFLP)法检测转化生长因子β1(TGF-β1)启动子区C-509T位点的变异并探讨其在肝纤维化中的作用．方法:根据TGF-β1启动子区基因设计引物, 在C-509T位设计Bsu36 I酶切位点,根据PCR 产物酶切结果判断该位点为C或T．观察对象为慢性乙型肝炎患者50例,乙型肝炎后肝硬化患者46例．结果:测序显示本文两株纯合子与TGF-β1启动子区序列同源性在99％以上,并在C-509T 位点出现预期变异:乙型肝炎和乙型肝炎后肝硬化两组都是以CT基因型为主,但是肝硬化组CC基因型(28.3％)高于TT基因型(19．6％), 而肝炎组TT基因型(22％)高于CC基因型(4％), 几组之间有显著性差异(P<0．01)．结论:本文建立的方法可用于TGF-β1启动子区C-509T住点基因多态性的检测,该位点CC 基因型可能与肝纤维化有关．

AIM： To establish a polymerase chain reactionrestriction fragment length polymorphism （PCRRFLP） method to detect the polymorphism of C-509T at the promoter region of transforming growth factor （TGF） β1 gene and explore its probable role in liver fibrosis. METHODS： Patients with chronic hepatitis B （n = 50） and liver cirrhosis （n = 46） were involved in this study. A polymerase chain reactionrestriction fragment length polymorphism （PCRRFLP） was established. A set of primers was designed according to the promoter region of TGF-β1 gene. Around C-509T was the enzyme digestion site for restriction endonuclease Bsu36 I. C or T was assured based on the enzymatic result of the polymerase chain reaction （PCR）products. RESULTS： Sequencing revealed 99% homogeneity between the two homozygous strains and the promoter region of TGF-β1 gene. The anticipated mutations appeared at position C-509T. The CT genotype prevailed in both the hepatitis and the liver fibrosis patients. The frequency of CC genotype （28.3%） was higher than that （19.6%） of TT genotype in liver fibrosis patients while the frequency of TT genotype （22%） was higher than that （4%） of CC genotype in hepatitis patients. There were significant differences between all the groups （P 〈 0.01）. CONCLUSION： The established method may be applied to detect the C-509T polymorphism at the promoter region of TGF-β1 gene. The CC genotype may be involved in liver fibrosis.