Soe Than Naing, Wu Yanrui, Tun Myo Win, Xu Xin, Hu Yue, Ruan Yonghua, Win Aung Ye Naung, Nyunt Myat Htut, Mon Nan Cho Nwe, Han Kay Thwe, Aye Khin Myo, Morris James, Su Pincan, Yang Zhaoqing, Kyaw Myat Phone, Cui Liwang
Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar.
Department of Pathogen Biology and Immunology, Kunming Medical University, Kunming, China.
Parasit Vectors. 2017 Jul 4;10(1):322. doi: 10.1186/s13071-017-2254-x.
The genetic diversity of malaria parasites reflects the complexity and size of the parasite populations. This study was designed to explore the genetic diversity of Plasmodium falciparum populations collected from two southeastern areas (Shwekyin and Myawaddy bordering Thailand) and one western area (Kyauktaw bordering Bangladesh) of Myanmar.
A total of 267 blood samples collected from patients with acute P. falciparum infections during 2009 and 2010 were used for genotyping at the merozoite surface protein 1 (Msp1), Msp2 and glutamate-rich protein (Glurp) loci.
One hundred and eighty four samples were successfully genotyped at three genes. The allelic distributions of the three genes were all significantly different among three areas. MAD20 and 3D7 were the most prevalent alleles in three areas for Msp1 and Msp2, respectively. The Glurp allele with a bin size of 700-750 bp was the most prevalent both in Shwekyin and Myawaddy, whereas two alleles with bin sizes of 800-850 bp and 900-1000 bp were the most prevalent in the western site Kyauktaw. Overall, 73.91% of samples contained multiclonal infections, resulting in a mean multiplicity of infection (MOI) of 1.94. Interestingly, the MOI level presented a rising trend with the order of Myawaddy, Kyauktaw and Shwekyin, which also paralleled with the increasing frequencies of Msp1 RO33 and Msp2 FC27 200-250 bp alleles. Msp1 and Msp2 genes displayed higher levels of diversity and higher MOI rates than Glurp. PCR revealed four samples (two from Shwekyin and two from Myawaddy) with mixed infections of P. falciparum and P. vivax.
This study genotyped parasite clinical samples from two southeast regions and one western state of Myanmar at the Msp1, Msp2 and Glurp loci, which revealed high levels of genetic diversity and mixed-strain infections of P. falciparum populations at these sites. The results indicated that malaria transmission intensity in these regions remained high and more strengthened control efforts are needed. The genotypic data provided baseline information for monitoring the impacts of malaria elimination efforts in the region.
疟原虫的遗传多样性反映了寄生虫种群的复杂性和规模。本研究旨在探索从缅甸东南部两个地区（与泰国接壤的瑞坚和妙瓦底）以及一个西部地区（与孟加拉国接壤的皎漂）采集的恶性疟原虫种群的遗传多样性。
共采集了2009年至2010年期间急性恶性疟原虫感染患者的267份血样，用于在裂殖子表面蛋白1（Msp1）、Msp2和富含谷氨酸蛋白（Glurp）基因座进行基因分型。
184份样本成功在三个基因上进行了基因分型。三个基因的等位基因分布在三个地区之间均有显著差异。MAD20和3D7分别是三个地区Msp1和Msp2中最常见的等位基因。bin大小为700 - 750 bp的Glurp等位基因在瑞坚和妙瓦底最为常见，而bin大小为800 - 850 bp和900 - 1000 bp的两个等位基因在西部的皎漂最为常见。总体而言，73.91%的样本包含多克隆感染，导致平均感染复数（MOI）为1.94。有趣的是，MOI水平呈现出妙瓦底、皎漂和瑞坚依次上升的趋势，这也与Msp1 RO33和Msp2 FC27 200 - 250 bp等位基因频率的增加相平行。Msp1和Msp2基因显示出比Glurp更高的多样性水平和更高的MOI率。PCR检测发现4份样本（2份来自瑞坚，2份来自妙瓦底）同时感染了恶性疟原虫和间日疟原虫。
本研究对缅甸两个东南部地区和一个西部邦的寄生虫临床样本在Msp1、Msp2和Glurp基因座进行了基因分型，揭示了这些地点恶性疟原虫种群的高度遗传多样性和混合菌株感染情况。结果表明这些地区的疟疾传播强度仍然很高，需要加强控制措施。这些基因型数据为监测该地区疟疾消除工作的影响提供了基线信息。
