Tehran University of Medical Sciences Journal of Arthropod-Borne Diseases 2322-1984 13 2 2018 10 12 206 213 Bentol Hoda Habibi-Shorkaei Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Afsaneh Motevalli-Haghi Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mehdi Nateghpour Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Research of Endemic Parasites of Iran, Tehran University of Medical Sciences, Tehran, Iran Leila Farivar Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Homa Hajjaran Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Soudabeh Etemadi Department of Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2019 06 16 Background: To overcome human malaria problem several solutions have been employed including extensive studies in the field of Plasmodia relevant antigens. The aim of this study was to determine allelic variation in the MSP1 gene of Plasmodium falciparum among some falciparum malaria-infected patients in Southeastern Iran. Methods: Twenty P. falciparum positive cases were enrolled from Sistan and Baluchistan Province, southeastern Iran in 2013–15. From each case, 1.5ml of peripheral blood was collected into EDTA contained tubes. Thick and thin blood smears were stained with standard Giemsa stain and were checked with conventional microscopical method. DNA was extracted from blood samples and amplification of block 2 MSP1 was performed using specific primers. Gel electropho­resis was done and results showed some amplification fragments corresponding to block 2 regions of Pf MSP1 gene. Finally, four samples from different allelic types were sent for sequencing process. Results: Fragments were different in size, so classified into six allelic types as kinds of 1–6 based on happening fre­quencies. Digestion of PCR products revealed two sub allelic types (A and B) within allelic types 2 and 3, but not in al­lelic types 1, 4, 5 and 6. Twenty percent of samples were sent for sequencing. Sequence alignment showed 78.95% to 91.83% identity between samples. Conclusion: Identity between samples and phylogenetic tree revealed that there is an extensive diversity range among isolates. Fifty percent of the isolates were under the risk of complicated malaria. Two of these patients (10%) needed special care and recovery was obtained after getting hospital services. https://jad.tums.ac.ir/index.php/jad/article/view/1142 https://jad.tums.ac.ir/index.php/jad/article/download/1142/457