海南省恶性疟原虫氯喹抗性相关基因pfcrt多态性分析

STUDY ON THE POLYMORPHISMS OF CHLOROQUINERESISTANT GENE pfcrt OF PLASMODIUM FALCIPARUM ISOLATES FROM HAINAN PROVINCE

目的了解海南省恶性疟原虫产生氯喹抗性是否与pfcrt基因中的关键性点突变有关。方法对45份采自海南省恶性疟患者血样,采用套式PCR法分别扩增pfcrt基因中含有第76位和220位氨基酸的多态性片段,并对扩增产物进行限制性内切酶酶切分析,观察是否存在突变位点。结果45个样本中,pfcrt基因发生K76T点突变的样本有28个,其中20个是抗性株,8个是敏感株;全部样本的pfcrt基因第220位氨基酸均发生A220S点突变。结论我国海南株恶性疟原虫产生氯喹抗性与发生在pfcrt基因中的K76T点突变有一定的关联。

Objective To identify whether point mutations existed in pfcrt genes of Plasmodium falciparum from Hainan Province and their relations with chloroquine resistance. Methods 45 blood samples were collected from falciparum malaria cases in Hainan Province. Nested PCR was used to amplify fragments of pfcrt genes including K76T and A220S mutations. PCR products were digested with different restriction endomucleases to detect whether point mutations existed in pfcrt genes. Results The pfcrt K76T mutation was detected in 28 of 45 isolates, 20 of them were chloroquineresistant and the other 8 were chloroquinesensitive. However, A220S mutation was detected in all isolates tested. Conclusion It was clear that a significant association existed between mutations in pfcrt, especially the K76T mutation, and the chloroquine resistance in P. falciparum isolates from Hainan Province .