云南的疟疾流行压力主要来自周边国家感染病例的持续输入，及时发现、正确诊断这些病例是防止疟疾在中国境内蔓延的关键。但由于疟原虫富组氨酸蛋白Ⅱ（PfHRPⅡ）的缺乏或变异，使得以此为检测靶蛋白的“免疫快速诊断卡（RDTs）”误诊恶性疟情况频繁发生，WHO对此高度关注。前期我们对PfHRPⅡ的基因Pfhrp2在云南的缺失调查发现，基因的部分缺失包括DNA链缺失长度不一、部位不同等，完全缺失率约为27%，在RDTs靶蛋白中增加B细胞表位活性高的裂殖子表面蛋白3或可弥补PfHRPⅡ缺乏、变异的不足。本课题拟：通过采用基因检测与表达、肽序列扫描等方法，对云南及周边国家恶性疟原虫的Pfhrp2基因缺失多态、肽链抗原表位进行检测，以揭示Pfhrp2基因完全缺失在研究地区的分布，阐释Pfhrp2基因部分缺失对RDTs诊断恶性疟的影响，研究结果除填补国内空白外，将为云南及周边东南亚国家改良RDTs产品提供依据

The malaria epidemic pressure in Yunnan Province is mainly caused by the continuous import of malaria cases infected in neighboring countries of Yunnan, and the timely discovery of these cases is the key to prevent malaria spread in china. However, because the lack or variation of Histidine-rich protein 2 (PfHRPII) which is detection target protein of malaria immune diagnostic card (RDTs) order to occur frequently missed diagnosis of falciparum malaria using RDTs, so WHO highly concerns about this. In our early survey, Yunnan we found that the Pfhrp2 of PfHRP II gene maybe exists two deletion forms of partial deletion and entire deletion in falciparum malaria cases isolates population. Further analysis shown that Pfhrp2 gene partial deletion included DNA chain length polymorphism and deletion location different polymorphism, the entire deletion rate maybe was 23% in P.falciparum population.These study results are relatively systematic and in the leading position in China. In this project, we intend to analyze the deletion, polymorphism as well as the sequence of antigen epitope of Pfhrp2 gene in P.falciparum of Yunnan and surrounding countries by the techniques of genetic testing, gene expression and peptide sequence scanning. At the same time, in order to meet the WHO needs of grasping relevant information, make up the lack of.theoretical understanding and provide the basis for selection and improvement of RDTs products in study areas, the regulation of the complete deletion of Pfhrp2 gene in P.falciparum and the impact of partly deletion of Pfhrp2 gene and its expression leading to the falciparum diagnosis of RDTs will be analysed in study areas .