DNA probes for detection of Marteilioides chungmuensis from the ovary of Pacific oyster Crassostrea gigas

The detection of the paramyxean parasite Marteilioides chungmuensis has been achieved only by using standard histological techniques or gross observations, which have a limited sensitivity for early diagnosis. In the present study, small subunit ribosomal DNA of the parasite was sequenced, and polymerase chain reaction (PCR) primers designed accordingly. It has been demonstrated that both the PCR and in situ hybridization techniques are specific for M. chungmuensis. Moreover, compared to traditional histological techniques and gross observation, the PCR diagnosis showed a far greater sensitivity. These new diagnostic tools based on molecular techniques can also be used for the elucidation of the parasite's life cycle and the identification of possible intermediate hosts.