Etemadi Soudabeh, Nateghpour Mehdi, Motevalli Haghi Afsaneh, Eslami Hamid, Mohebali Mehdi, Setayesh Neda, Farivar Leila, Teimouri Aref
Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Department of Parasitology and Mycology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
Iran J Public Health. 2020 May;49(5):981-988.
Circumsporozoite protein (CSP) is one of the most important surface sporozoite antigens in malaria, recently considered as a candidate for vaccination. Considering the importance of CSP, this study was conducted to investigate the polymorphism and genetic diversity of Circumsporozoite Protein () in the southeastern region of Iran during 2015-2016.
To investigate polymorphism and genetic diversity, 20 blood samples were collected from patients with , then DNA was extracted and amplified using partial sequence of CSP gene. Polymerase chain reaction (PCR) products were sequenced and compared to sequences from genomic databases using BLAST. Genetic evaluation and phylogenic analysis were performed using MEGA7 and DnaSP5 software's on 38 sequences include 20 sequences of our study and 18 sequences of Gene Bank.
Eleven isolates were VK210 genotype and 9 isolates contained VK247. The result of variable segregation nucleotide site indicated that the differentiation of sequences in CSP were 25.67% in our 20 samples which are less than the 38 samples with a value of 26.67%. Comparing the ratio of dN/dS regions in the CSP gene indicates that the CSP varies more synonymously and amino acid has lower variation. Out of 38 samples, 35 unique haplotypes were identified based on 1042 nucleotide sequences in CSP, showing a variation percentage of 99.4%.
The Tajima D analyses showed that CSP gene in had a positive number in the total analyzed sequences, which means that the mutations are in order to select positive evolution.
环子孢子蛋白（CSP）是疟疾中最重要的表面子孢子抗原之一，最近被视为疫苗接种的候选抗原。鉴于CSP的重要性，本研究旨在调查2015 - 2016年伊朗东南部地区环子孢子蛋白（）的多态性和遗传多样性。
为调查多态性和遗传多样性，从疟疾病人身上采集了20份血样，然后提取DNA并使用CSP基因的部分序列进行扩增。对聚合酶链反应（PCR）产物进行测序，并使用BLAST与基因组数据库中的序列进行比较。使用MEGA7和DnaSP5软件对包括本研究的20个序列和基因库的18个序列在内的38个序列进行遗传评估和系统发育分析。
11个分离株为VK210基因型，9个分离株含有VK247。可变分离核苷酸位点的结果表明，我们的20个样本中CSP序列的分化率为25.67%，低于38个样本的26.
