MICA基因第5外显子与乙肝后肝硬变的相关性研究

目的研究MICA基因多态性、sMICA分子与乙肝后肝硬化（livercirrhosis，LC）的相关性。方法采用MICA—STR微卫星基因分型技术检测101例HBsAg阳性LC患者和141例健康对照者MICA基因第5外显子的基因多态性，并进行统计学分析。结果在101例湖南汉族HBsAg阳性LC患者中检测到5种MICA基因第5外显子等位基因，频率分别为：MICA＊A4（10．9％），MICA＊A5（37．1％），MICA＊A5．1（34．2％），MICA＊A6（7．4％），MICA＊A9（10．4％）。15种基因型分别为MICA＊A4／A4，MICA＊A4／A5．MICA＊A4／A5．1．MICA＊A4／A6，MICA＊A4／A9，MICA＊A5／A5，MICA＊A5／A5．1，MICA＊A5／A6．MICA＊A5／A9，MICA＊A5．1／A5．1，MICA＊A5．1／A6，MICA＊A5．1／A9，MICA＊A6／A6，MICA＊A6／A9，MICA＊A9／A9。MICA＊A5．1基因与LC发病正相关（P=0．042），OR值为1．398，与患者性别无关（χ^2=0．08，P=0．778）。结论MICA＊A5．1基因与乙肝后LC发病正相关，提示该基因可能是乙肝后出现LC的重要易感基因。

The correlation between liver cirrhosis by hepatitis B and MICA exon 5 gene

Objective To study MICA gene polymorphism and the correlation of sMICA with HBsAg positive liver cirrhosis （LC）. Methods MICA-STR mierosatellite genotyping was used to characterize the polymorphism of MICA exon 5 in 101 patients with HBsAg positive LC and 141 normal controls, and the relevance index between them was calculated. Results 5 kinds allelic gene and their frequencies were identified in MICA exon 5 and showed as below： MICA ＊ A4 （ 10.9% ）, MICA ＊ A5 （37.1%）, MICA ＊ A5.1 （34.2%）, MICA ＊ A6 （7.4%）, MICA ＊ A9 （ 10.4% ）. 15 genotypes including MICA ＊ A4/A4, MICA ＊ A4/A5, MICA A4/A5.1, MICA ＊ A4/A6, MICA ＊ A4/A9, MICA ＊ A5/A5, MICA ＊ A5/A5.1, MICA ＊ A5/A6, MICA ＊ A5/ A9, MICA ＊ A5. 1/A5.1, MICA ＊ A5. 1/A6, MICA ＊ A5.1/A9, MICA ＊ A6/A6, MICA ＊ A6/A9, MICA ＊ A9/ A9. Only MICA ＊ A5.1 was positively associated with LC onset （P= 0.042）, OR was 1.398, but was not associated with gender （χ^2= 0.08,P= 0.778）. Conclusion MICA ＊ A5.1 gene may be an important susceptibility gene leading to LC after infected with hepatitis B according to the positive correlation between MICA ＊ A5.1 and hepatitis B induced LC.