HRM技术检测炎症性肠病患者TPMT的基因多态性

目的应用HRM技术检测炎症性肠病(IBD)患者TPMT基因多态性,进而探索IBD患者TPMT基因型与硫唑嘌呤(AZA)致骨髓抑制的关系。方法采用聚合酶链反应-高分辨熔解曲线(PCR-HRM)与Sanger法序列测定相结合的方法,对82例IBD患者和53名健康志愿者TPMT基因第7、10外显子进行检测。结果 IBD患者中TPMT*1/*3C杂合子4例,健康对照者中TPMT*1/*3C杂合子2例。未检测出TPMT*3A和TPMT*3B型突变。IBD患者4例出现骨髓抑制的患者中,1例是TPMT*1/*3C杂合子;其余3例为TPMT野生型。结论 TPMT*3C(A719G)基因突变在中国的IBD患者中较TPMT*3A(G460A/A719G)、TPMT*3B(G460A)发生率高,而存在此基因突变的IBD患者对硫唑嘌呤不能耐受,导致骨髓抑制。然而TPMT基因突变只能解释部分AZA治疗IBD导致骨髓抑制的病例。

TPMT gene polymorphism of the HRM technology in IBD patients

Objective To detect the gene polymorphism of the inflammatory bowel disease ~ ll~LJ） patients, Iartner more, to discuss the relationship between the genotype of TPMT and AZA induced myelotoxicity in the patients with IBD. Methods Three commom mutation alleles of TPMT [ TPMT ＊ 3A （G460A/A719G）, TPMT ＊ 3B （G460A）, TPMT ＊ 3C （ATIgG：） ] were detected by polymerasechain reacti0n：high resolutidn melting and sequencing in 82 IBD patients and 53＇ healthy ：Chin~e peopte; Resuits） F8ur eases of heterozygote TPMT ＊ 1/＊ 3C were found in IBD pa- tients. No TPMT＊ 3A or TPMT＊ 3B was found;. =Bone marrow supDression occurred in four of the patients who received AZA, but only one of them had the TPMT ＊ 1/＊ 3C mutation, others were wild-type homozygote. Conclusion The fre- quency of TPMT ＊ 3C（A719G） mutation is more than TPMT ＊ 3A（G460A/A719G） and TPMT ＊ 3B（G460A） mutation in Chinese IBD patients. Patient who has the TPMT ＊ 3C（A719G）mutation is very likely to have the bone marrow sup- pression. But mutantion of TPMT gene could just partially explain the AZA induced myelotoxicity.