Polymorphism in the gene encoding the Pfs48/45 antigen of Plasmodium falciparum.: XI.: Asembo Bay Cohort Project
Polymorphism in the gene encoding the Pfs48/45 antigen of Plasmodium falciparum.: XI.: Asembo Bay Cohort Project
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DOI：
10.1016/s0166-6851(01)00386-3
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发表时间：
2002-01-01
影响因子：
1.5
通讯作者：
Lal, AA
中科院分区：
文献类型：
--
作者：
Escalante, AA;Grebert, HM;Lal, AA
我们研究了来自肯尼亚西部的恶性疟原虫寄生虫的编码传播阻断疫苗抗原 Pfs48/45 的基因的遗传多样性，并将其与泰国、印度和委内瑞拉的寄生虫种群进行了比较。我们报告了 44 个完整的新序列。总体而言，与其他红细胞前和血液阶段抗原相比，该抗原的多态性较低。与其他恶性疟原虫抗原相反，每个同义位点的同义取代数量超过每个非同义位点的非同义取代数量。我们发现肯尼亚寄生虫的 Pfs48/45 基因比其他地理来源的寄生虫更具多态性。我们的分析表明，积极的自然选择参与了观察到的多态性的维持。没有发现基因内重组的证据。 F-st 值显示印度和泰国之间的基因流动水平较高，但肯尼亚、东南亚和委内瑞拉寄生虫之间的基因流动受到很大限制。没有等位基因可以与特定地理区域联系起来。这项研究的结果表明，这种配子体抗原与其他无性血期抗原一样，面临着选择压力。 (C) 2002 Elsevier Science B.V. 保留所有权利。
We have investigated the genetic diversity of the gene encoding the transmission-blocking vaccine antigen Pfs48/45 of Plasmodium falciparum parasites from western Kenya and compared it with parasite populations front Thailand, India, and Venezuela. We report 44 complete new sequences. Overall, the antigen is less polymorphic as compared with other pre-ecrythrocytic and blood stage antigens. Contrary to other P. falciparum antigens, the number of synonymous substitutions per synonymous site exceeds the number of non-synonymous substitutions per non-synonymous site. We have found that the Pfs48/45 gene of Kenyan parasites is more polymorphic than parasites from other geographic origins. Our analysis reveals that positive natural selection is involved in the maintenance of the observed polymorphism. No evidence of intragenic recombination was found. F-st values reveal high levels of gene flow between India and Thailand, however, there are strong constraints in gene flow among Kenyan, Southeast Asian, and Venezuelan parasites. No alleles could be linked to a specific geographic region. The results of this study suggest that this gametocyte antigen, like other asexual blood stage antigens, is under selection pressure. (C) 2002 Elsevier Science B.V. All rights reserved.