Wong Kenneth H S, Ng G C, Lin Raymond T P, Yoshikawa H, Taylor Mark B, Tan Kevin S W
Laboratory of Molecular and Cellular Parasitology, National University of Singapore, Singapore 5 Science Drive 2, Singapore 117597, Singapore.
Parasitol Res. 2008 Mar;102(4):663-70. doi: 10.1007/s00436-007-0808-0. Epub 2007 Dec 7.
Blastocystis is an enteric protozoan parasite commonly found in humans and animals. Phylogenetic and genotypic analyses have shown that Blastocystis exhibits extreme genetic diversity, and humans are host to a number of zoonotic isolates. In the present study, the prevalence of Blastocystis in 276 stool samples from a hospital in Singapore was examined, and for the first time, riboprinting using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to determine the genetic diversity of the Blastocystis isolated from the Singapore population. The prevalence rate was determined to be 3.3% (9/276), and Blastocystis displaying two main ribotypes were isolated. As a comparison, we performed PCR-RFLP using two different published methodologies, and both methods allowed the isolates to be divided into two distinct groups based on their riboprint patterns. According to a recently proposed classification scheme, 78% (7/9) of the isolates were of subtype 3, while 22% (2/9) were subtype 1. The predominance of subtype 3 in an urbanized city state such as Singapore is in agreement with the idea that subtype 3 is a genotype of human origin.
芽囊原虫是一种常见于人和动物体内的肠道原生动物寄生虫。系统发育和基因分型分析表明，芽囊原虫具有极高的遗传多样性，人类是多种人畜共患分离株的宿主。在本研究中，对新加坡一家医院的276份粪便样本进行了芽囊原虫感染率检测，并首次采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）核糖体印记法来确定从新加坡人群中分离出的芽囊原虫的遗传多样性。检测得出感染率为3.3%（9/276），并分离出显示两种主要核糖体分型的芽囊原虫。作为对比，我们使用两种已发表的不同方法进行PCR-RFLP，两种方法均能根据核糖体印记模式将分离株分为两个不同的组。根据最近提出的分类方案，78%（7/9）的分离株为3型亚型，而22%（2/9）为1型亚型。在新加坡这样的城市化城邦中3型亚型占主导地位，这与3型亚型是人类源基因型的观点一致。
