用微卫星分析我国不同地区间日疟原虫的种群结构

Analysis of the population structure of Plasmodium vivax isolates from different areas in China using microsatellites

目的了解我国不同疟疾流行区间日疟原虫种群结构和遗传多样性特征，积累我国间日疟原虫遗传相关数据。方法收集云南、海南、河南流行区间日疟患者血样，血涂片鉴定间日疟原虫阳性者抽提血液基因组，采用巢式／半巢氏PCR方法扩增特异性2．21微卫星片段，对扩增阳性产物进行基因扫描检测，根据检测微卫星的重复序列进行STR分型，并应用GENALEX软件计算等位基因频率、等位基因数目以及期望杂合度（expectedheterozygosity，Hc）。结果间日疟原虫2．21微卫星在不同地区间日疟原虫样本中呈现高度的多态性，其等位基因数目变化范围为4～9，期望杂合度为0．613-0．853，比较不同地区，云南地区间日疟原虫等位基因数目为9，期望杂合度为0．853，变异度最高。结论我国不同地区间日疟原虫基因组具有较高的遗传多样性，其种群结构具有地区特征，这可能与各种群传疟媒介种类不同及地理环境差异等相关。

Objective To investigate the population structure and genetic diversity of Plasmodium vivax isolates from malaria-endemic areas in China, and to set up genetic database of vivax malaria. Methods Blood samples of symptomatic patients that were positive for P. vivax by microscope were collected from Yunnan, Hainan and Henan provinces and used for nested PCR amplification of DNA fragment containing microsatellite loci and detection of the microsatellite by Genescan. Then GENALEX software was used to calculate haplotype frequency, number of alleles and expeted heterozygosity （ He ）. Results The length of 2.21 microsatellite was highly variable in P. vivax isolates from different areas in China. The number of the microsatellite alleles varied from 4 to 9, and expected heterozygosity （ Ho ） was 0. 613 - 0. 853. The microsatellite showed the highest diversity in the isolates from Yunnan where the number of allele is 9 and Ho means 0. 853 compared to those in other areas. Conclusion The P. vivax isolates from different areas in China showed high genetic diversity and regionally-centered differences.