Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 12 3 2017 09 17 433 440 In Young OH Dept. of Biomedical Laboratory Science, College of Health Sciences, Eulji University, Seongnam-si, Gyeonggi-do, Korea Kyung Tae KIM ALPHAGENE Co., Ltd., Singu University, Business Incubation Center, Seongnam, Korea Ho Joong SUNG Dept. of Biomedical Laboratory Science, College of Health Sciences, Eulji University, Seongnam-si, Gyeonggi-do, Korea AND Dept. of Senior Healthcare, BK21 Plus Program, Graduate School, Eulji University, Daejeon, Korea 2017 09 17 2017 09 17 Background: Dirofilaria immitis, a filarial nematode, is the most important parasite-affecting dogs, causing cardiopulmonary dirofilariasis. Current diagnostic tools for detecting D. immitis include morphological assays, antigen detection, and X-ray. Herein, we developed a method for the molecular detection of D. immitis in blood using polymerase chain reaction (PCR). Methods: The study was conducted at Eulji University, Republic of Korea in 2016. To detect D. immitis-specific gene regions, we aligned the cytochrome c oxidase subunit I (COI) genes of seven filarial nematodes and designed primers targeting the unique region. We used dog glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-targeted primers as the internal control. We conducted PCR-amplified genomic DNA from canine blood samples. The products were confirmed by sequencing. Results: Gene alignment revealed a D. immitis COI-specific gene region, and the activity of designed primers was confirmed by PCR and sequencing. Plasmid DNA made from the PCR products was a positive control. The limit of detection for our method was 50 copies. The D. immitis COI and dog GAPDH genes could be discriminated from blood samples simultaneously. Conclusion: This study provides a method for highly specific and sensitive molecular diagnosis of D. immitis used as a diagnostic and therapeutic tool from the early stage of infection. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/1775 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/1775/766