Rapid and sensitive detection of Singapore grouper iridovirus by loop-mediated isothermal amplification

Aims: The aim of this paper was to develop a loop-mediated isothermal amplification (LAMP) method for rapid, sensitive and inexpensive detection of Singapore grouper iridovirus (SGIV) in grouper (GP), Epinephelus sp. Methods and Results: A set of six specific primers was designed by targeting the SGIV ORF-014L. With Bst DNA polymerase large fragment, the target DNA can be amplified as early as 20 min at 65 degrees C in a simple water bath. The detection limit is about 0.02 fg (equivalent to 6.3 copies) of plasmid ORF-014L. LAMP products could be judged with three different methods. There were no cross-reactions with seven other aquatic animal viruses indicating high specificity of the LAMP. The LAMP method was applied to detect SGIV in virus-infected GP cells and GP tissues effectively. Conclusions: The LAMP described in this study is a cheap, sensitive, specific and rapid protocol for the detection of SGIV in cells and in GP tissues. Significance and Impact of the Study: The developed LAMP method can be simply applied both in field condition and in laboratory operation for specific detection of SGIV infection.