Biology Department, College of Education for Women, Tikrit University, Iraq.
Ann Parasitol. 2022;68(2):391-398. doi: 10.17420/ap6802.445.
Blastocystis hominis is an intestinal protozoan that inhabits the large intestine of humans and a wide range of animals. Blastocystis species has a worldwide distribution. The current study aimed to determine the prevalence and the genetic variety of Blastocystis sp. in Iraqi children in Salah AL-Deen province, Iraq. 150 faecal samples were collected from children (5-10 years old) who attended the Salah AL-Deen hospital during the period from March to November 2020. The results revealed that 33.3% of children (50 out of 150) were found infected with Blastocystis sp., when the polymerase chain reaction (PCR) was used. The presence of ST3 gene was at a band of 526 bp where this gene was observed in 11 samples out of 50 samples. The results also showed significant differences in the prevalence rate between rural and urban regions; between symptomatic and asymptomatic children, and between children who contacted domestic animals and those who did not contact animals (P<0.05). No significant differences in the prevalence rate were between different age groups (P>0.05). Regarding the genetic variation in subtype 3(ST3) revealed in phylogenetic tree analysis, there were three variations (transversion, deletion, and transition) which were detected through the sequence alignment, also the similarity was 97% with the sequences of Blastocystis sp. registered in GenBank. The Iraqi ST3 isolate was registered with ID: OL410286 in GenBank.
人芽囊原虫是一种寄生于人类和多种动物大肠的肠道原生动物。芽囊原虫在世界范围内广泛分布。本研究旨在确定伊拉克萨拉赫丁省儿童中芽囊原虫的流行率和遗传多样性。2020 年 3 月至 11 月期间，从萨拉赫丁医院就诊的 5-10 岁儿童中采集了 150 份粪便样本。结果显示，当使用聚合酶链反应（PCR）时，33.3%的儿童（150 份中的 50 份）被发现感染了芽囊原虫。ST3 基因的存在位于 526 bp 的条带处，在 50 份样本中的 11 份中观察到该基因。结果还表明，城乡地区、有症状和无症状儿童以及接触过家畜和未接触过动物的儿童之间的流行率存在显著差异（P<0.05）。不同年龄组之间的流行率无显著差异（P>0.05）。关于系统发育树分析中揭示的 3 型（ST3）的遗传变异，通过序列比对检测到三种变异（转换、缺失和转换），并且与 GenBank 中注册的芽囊原虫序列的相似性为 97%。伊拉克 ST3 分离株在 GenBank 中注册为 OL410286。
