Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 8 4 2013 12 15 510 515 EN Mahdi Mosayebi Dept. of Parasitology, Medical Faculty, Arak University of Medical Sciences, Arak, Iran. Abdolhossein Dalimi Asl Dept. of Parasitology, Medical Sciences Faculty, University of Tarbiat Modarres, Tehran, Iran. Mohammad Moazzeni Dept. of Immunology, Medical Sciences Faculty, University of Tarbiat Modarres, Tehran, Iran. Ghasem Mosayebi Dept. of Immunology, Medical Faculty, Arak University of Medical Sciences, Arak, Iran. 2015 10 14 Background: The objective of this study was to investigate HLA-DRB1*and DQB1* allelic polymorphisms in Iranian patients with hydatidose. This is the first survey dealing with the correlation between HLA-DRB1* and DQB1* al-leles and cystic echinococcosis in Iranian patients. Methods: The study was carried out on 56 patients with confirmed cystic echi-nococcosis and 30 apparently healthy individuals living in Arak- Markazi Prov-ince by HLA-DRB1 and DQB1 typing through PCR-SSP method. The first step was to identify the patients and blood sampling. DNA was prepared from whole blood and PCR-SSP with 31 primer mixes for per sample was used. PCR reaction mixtures were loaded in agarose gels and bands were observed under UV illumination and gel document after electrophoresis. Analysis of results was carried out with specific softwares and frequency and interpretation tables for calculation of P-value in χ2 test were provided via Fisher΄s exact test. Signifi-cant samples were analyzed by logistic regression and odds-ratios were calculat-ed. Results: A statistically significant positive association was found between HLA-DQB1*03 and the resistance to cystic echinococcosis (P<0.02) (odds-ratio=2.87). Conclusion: Immunogenetic susceptibility to unilocular hydatidose varies ac-cording to the HLA antigens in Arak, Markazi Province, and DQB1*03 mole-cules are associated with the level of immune response to parasite antigens. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/461 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/461/506