Hope M, Foley D H, McManus D P
Molecular Parasitology Unit, Queensland Institute of Medical Research, Brisbane, Australia.
Acta Trop. 1995 Oct;60(2):101-8. doi: 10.1016/0001-706x(95)00113-s.
A number of discrete strains of Schistosoma japonicum have been described of which those from China and the Philippines are the most important in terms of public health significance. The strains have previously been shown to differ in a number of biological characteristics and isoenzyme analysis has established that Chinese and Philippine S. japonicum are, especially, quite distinct. As few direct genetic differences have been identified, with nuclear and mitochondrial genetic markers being shown earlier to be highly conserved between the two forms (Bowles et al., 1993), enzyme electrophoresis was performed to re-evaluate whether the two strains are as genetically diverse as field and laboratory maintained isolates previously examined using this approach. Some allelic differences were evident between Chinese and Philippine S. japonicum but the genetic distance (a measure of genetic relatedness), D = 0.272, between the two strains was, however, considerably smaller than the earlier obtained estimates of D > 0.4-0.575. In addition to the enzyme studies, restriction patterns, obtained using 4-base cutting restriction enzymes and hybridisation with DNA probes comprising the entire ribosomal DNA (rDNA) repeat unit of S. mansoni, were indistinguishable between the Chinese and Philippine forms of S. japonicum, thereby re-emphasising their remarkable similarity at the genetic level.
已经描述了许多日本血吸虫的离散菌株，其中来自中国和菲律宾的菌株在公共卫生意义方面最为重要。这些菌株先前已被证明在许多生物学特性上存在差异，同工酶分析已确定中国和菲律宾的日本血吸虫尤其明显不同。由于几乎没有发现直接的遗传差异，之前核和线粒体遗传标记显示这两种形式之间高度保守（Bowles等人，1993年），因此进行了酶电泳，以重新评估这两种菌株在遗传上是否像之前使用这种方法检测的野外和实验室保存的分离株那样具有多样性。中国和菲律宾的日本血吸虫之间存在一些等位基因差异，但两种菌株之间的遗传距离（遗传相关性的一种度量）D = 0.272，然而，这比之前获得的D > 0.4 - 0.575的估计值要小得多。除了酶研究之外，使用4碱基切割限制酶获得的限制图谱以及与包含曼氏血吸虫整个核糖体DNA（rDNA）重复单元的DNA探针杂交，在中国和菲律宾的日本血吸虫形式之间没有区别，从而再次强调了它们在遗传水平上的显著相似性。
