Grupo de Bioquímica y Biología Celular, Instituto Nacional de Salud, Bogotá, Colombia.
Infect Genet Evol. 2013 Aug;18:183-90. doi: 10.1016/j.meegid.2013.05.017. Epub 2013 May 25.
Colombia has four main malaria transmission zones. In vivo efficacy studies carried out in these areas showed big differences in the response of Plasmodium falciparum to treatment with sulphadoxine-pyrimethamine. In addition, there is still insufficient information about the genetics of P. falciparum populations. The objective of this study was to determine the haplotypes in dhfr and dhps genes of P. falciparum circulating in two distinct endemic zones. Samples from patients with non-complicated P. falciparum malaria were collected: 135 from Tumaco and 206 from Tierralta. Alleles 108 and 51 of the dhfr gene, and 437 and 540 of the dhps gene were analyzed by PCR/enzymatic restriction, while alleles 59 and 164 (dhfr), and 581(dhps) by PCR/dot blot/hybridization. Five different haplotypes were found, of which the triple mutant 51I/C59/108N/I164/437G/K540/A581 was the most frequent (54.6%). In Tumaco, the parasites with wild haplotype predominated, while mutant parasites predominated in Tierralta. Another interesting finding is the presence of the C59R mutation in the dhfr gene in two samples, a mutation rarely found in South America. These data provide information about parasite population genetics and highlight the importance of starting a long term molecular surveillance program.
哥伦比亚有四个主要的疟疾传播区。在这些地区进行的体内疗效研究表明，恶性疟原虫对磺胺多辛-乙胺嘧啶治疗的反应存在很大差异。此外，关于恶性疟原虫种群的遗传信息仍然不足。本研究的目的是确定在两个不同流行区循环的恶性疟原虫 dhfr 和 dhps 基因的单倍型。收集了来自非复杂性恶性疟患者的样本：来自 Tumaco 的 135 份和来自 Tierralta 的 206 份。通过 PCR/酶切限制性分析 dhfr 基因的 108 和 51 等位基因，以及 dhps 基因的 437 和 540 等位基因，通过 PCR/斑点印迹/杂交分析 dhfr 基因的 59 和 164 等位基因，以及 dhps 基因的 581 等位基因。发现了五种不同的单倍型，其中三重突变 51I/C59/108N/I164/437G/K540/A581 最为常见（54.6%）。在 Tumaco，野生型寄生虫占优势，而在 Tierralta，突变型寄生虫占优势。另一个有趣的发现是在两个样本中存在 dhfr 基因的 C59R 突变，这种突变在南美洲很少见。这些数据提供了有关寄生虫种群遗传学的信息，并强调了启动长期分子监测计划的重要性。
