Howard J, Carlton J M, Walliker D, Jensen J B
Brigham Young University, Microbiology Department, Provo, Utah 84602, USA.
J Parasitol. 1996 Dec;82(6):941-6.
Effectiveness of random amplified polymorphic DNA (RAPD), a technique using 1 10-base primer to amplify random segments of genomic DNA, and some of its possible uses were tested in the A + T-rich genome of Plasmodium falciparum. The best concentrations of MgCl2, 60% G + C primer, and DNA were determined to be 4.0 mM, 0.4 microM, and 90-180 ng/15 microliters reaction, respectively. Use of 30% G + C primers did not allow amplification to occur. Application of RAPD to DNA of parent and progeny clones from a P. falciparum cross showed that polymorphisms identified in the parentals and tracked in the progeny were inherited in a Mendelian fashion and that RAPD-identified polymorphisms could be used as genetic markers. Some of these polymorphic markers were located on more than 1 chromosome, whereas others were specific for a single chromosome. Two of these markers, each located on chromosome 3 of 1 of the parental parasites, were missing from 2 of the 18 progeny, suggesting that deletions, or crossover events had occurred. RAPD markers also identified a higher number of nonparental-type progeny than expected, thus confirming previous observations for high genetic variability in malaria parasites.
随机扩增多态性DNA(RAPD)是一种使用10碱基引物扩增基因组DNA随机片段的技术,本研究在恶性疟原虫富含A + T的基因组中测试了该技术的有效性及其一些可能的用途。确定MgCl2、60% G + C引物和DNA的最佳浓度分别为4.0 mM、0.4 microM和90 - 180 ng/15微升反应体系。使用30% G + C引物无法实现扩增。将RAPD应用于恶性疟原虫杂交亲本和子代克隆的DNA,结果表明在亲本中鉴定出并在子代中追踪到的多态性以孟德尔方式遗传,并且RAPD鉴定的多态性可作为遗传标记。其中一些多态性标记位于不止一条染色体上,而其他一些则特定于一条染色体。这些标记中的两个,每个位于一个亲本寄生虫的3号染色体上,在18个子代中的2个中缺失,这表明发生了缺失或交叉事件。RAPD标记还鉴定出比预期更多的非亲本类型子代,从而证实了先前关于疟原虫高遗传变异性的观察结果。