广州地区人群中硫嘌呤甲基转移酶基因的等位基因频率及分布

目的：了解硫嘌呤甲基转移酶(Thiopurme S-methyltransferase，TPMT)基因常见的遗传多态性在广州地区人群中的分布及其频率。方法：应用聚合酶链反应-等位基因特异性扩增(PCR-ASA)和聚合酶链反应-限制性片段长度多态性分析(PCR-RFLP)对文献报道的TPMT基因中三种常见的基因突变(G238C、G460A和A719G)进行检测。结果：在我们调查的人群中只检测到A719G(TPMT／3C)，其频率为0．7％(3／392)；该突变基因在人群中以杂合子形式存在，基因型频率为1．5％(3／196)，未发现突变型纯合子，亦未检测到另外两种基因突变。结论：广州地区人群中TPMT等位基因的频率及分布与白人存在明显差异，与黑人及日本人较为接近，但频率更低。

Alleles frequency of thiopurine methyltransferase gene in the populations of guangzhou area

Objective:To gain an insight into the distribution and frequency of common genetic polymorphism of the thiopurine methyltransferase (TPMT) gene in the populations of GuangZhou area.Method:Three kinds of gene mutations (G238C, G460A and A719G) reported by others were detected by using polymerase chain reaction allele specific amplification (PCR ASA) and polymerase chain reaction restricted fragment length polymorphism (PCR RFLP) analysis.Result:Only TPMT/3C (A719G) mutant allele in heterozygotes was found in 3/196 ( 1.5 %; 3/392 alleles, 0.7 %) Chinese individuals of our investigated populations, and the TPMT/3C mutant allele in homozygote and other mutant alleles were not detected.Conclusion:The distribution and freguency of TPMT alleles in the populations of GuangZhou area are different from those of Caucasian populations but similar to those of African and Japanese populations, while the frequency reported by us is lower.