NRAMP1基因INT4和3’UTR位点多态性与肺结核易感性的研究

目的 探讨人类自然抵抗相关巨噬细胞蛋白1（NRAMP1）基因INT4和3＇UTR位点多态性与中国北方汉族成人肺结核发病的关系.方法 采用1：1配对的病例对照研究设计,用聚合酶链反应-限制性片段长度多态性分析方法检测NRAMP1基因中INT4和3＇UTR两个多态性位点,对与肺结核相关的危险因素进行问卷调查,进行单因素和多因素条件logistic回归分析,同时对基因型与肺结核病变的性质和程度进行研究.结果 对124对研究对象进行了INT4和3＇UTR两个多态性位点的基因分型,3＇UTR TGTG＋/del基因型病例组频率显著高于对照组,粗OR值（95%CI）为2.923（1.557～5.487）.病例组和对照组INT4各基因型频率比较差异均无统计学意义.对17个环境危险因素进行了单因素分析,在多因素分析中调整卡痕、体重指数、人均居住面积、家族史4个因素后,3＇UTR TGTG＋/del基因型仍与肺结核显著相关,调整OR值（95%CI）为2.955（1.369～6.381）.在INT4不同基因型中,病例组和对照组肺结核病变性质差异具有统计学意义（x2=9.634,P＜0.05）.结论 NRAMP1基因3＇UTR位点多态性可能是中国北方汉族成人肺结核的易感因素,而INT4多态性可能与肺结核的病变性质有关系.

Study on the association of INT4 and 3' UTR polymorphism of natural-resistance-associated macrophage protein 1 gene with susceptibility to pulmonary tuberculosis

OBJECTIVE: To investigate the association between natural-resistance-associated macrophage protein 1 (NRAMP1) gene polymorphisms and susceptibility to pulmonary tuberculosis (TB) in Han nationality from Northern part of China. METHODS: A 1:1 matched case-control study was adopted. Polymerase chain reaction and restriction fragment length polymorphism technique were used to type the two NRAMP1 polymorphisms: INT4 and 3'UTR. Information on environmental-related risk factors and pathological changes of tuberculosis was collected using a pre-tested standard questionnaire. Univariate and multivariate conditional logistic analyses were conducted using SPSS for window software. RESULTS: A sample consisting 124 pairs of cases and controls was studied. Univariate analysis demonstrated that the 3'UTR TGTG+/del genotype occurred more frequently in the cases than in the controls, with crude OR (95% CI) being 2.923 (1.557 - 5.487). No significant association was observed between TB and INT4 polymorphism. In multivariate analysis, associations of TB and 3'UTR TGTG+/del genotype remained, after adjusting for scar of bacillus Calmette-Guérin vaccine, marriage status, body mass index and exposure history. Adjusted OR (95% CI) was 2.955 (1.369 - 6.381). Again, no significant association between INT4 polymorphism and TB was found. Among different INT4 genotypes, the pathological characters of pulmonary tuberculosis were also found different (chi(2) = 9.634, P < 0.05). CONCLUSION: Polymorphism of 3'UTR locus in NRAMP1 gene might affect their susceptibility to TB in Han nationality living in the northern part of China, and polymorphism of INT4 might affect the pathological characters of tuberculosis.