反式激活因子（class Ⅱ transactivator，CⅡTA）是调控MHCⅡ类基因表达水平的限速因子，故将CⅡTA作为慢性乙型肝炎（chronic hepatitis B， CHB）候选基因，分析其单核苷酸多态性（single nucleotide polymorphism， SNP）与CHB易感性的关联。以福建医科大学附属闽东医院汉族患者为基础进行病例对照研究，其中596例CHB患者为病例组，313例HBV自限性感染者为对照组。采用Haploview 4.2软件筛选出CⅡTA基因的15个标签SNP，再用多重高温连接酶检测反应对所选标签SNP进行基因型检测。结果显示，CⅡTA基因内含子rs13333382［TT+TA vs AA： P=0.003， OR=0.65， 95%可信区间（confidence interval， CI）为0.49～0.87］和rs4780335（CC+CG vs GG： P=9.40×10-5， OR=0.55， 95%CI为0.41～0.74）多态性与HBV自限性感染呈正相关，而3＇非翻译区rs1139564 （TT+TC vs CC： P=0.002， OR=1.61， 95%CI为1.19～2.16）多态性可增加CHB风险。因此，作者认为CⅡTA基因多态性与HBV感染结局存在关联。

To investigate the possible association between the single nucleotide polymorphism (SNP) of CⅡTA (class Ⅱ transactivator) and the susceptibility to chronic hepatitis B(CHB), a hospital-based case-control study was conducted in 596 patients with CHB, and 313 patients with HBV self-limiting infection served as the control group. All individuals were of Han nationality. The 15 tag SNP of CⅡTA were screened by Haploview 4.2 software, and the selected SNP were genotyped by iMLDR method. The results showed that the CⅡTA gene intron rs13333382 (TT+TA vs AA: P=0.003, OR=0.65, 95%CI, 0.49-0.87) and rs4780335 (CC+CG vs GG: P=9.40×10-5, OR=0.55, 95%CI, 0.41-0.74) polymorphisms were positively correlated with HBV self-limiting infection, while the 3' untranslated region rs1139564 (TT+TC vs CC: P=0.002, OR=1.61, 95%CI, 1.19-2.16) polymorphism could increase the risk of CHB. Therefore, our study suggests that the CⅡTA gene polymorphism is associated with the outcome of HBV infection.