In year 2006, Dr. Kathy F. J. Tang (University of Arizona, USA) had an article releasing two types of IHHNV-related sequence in the genome of P. monodon from Africa and Australia. She also mentioned that false-positive results may come from applying IQ2000TM IHHNV kit.
We accordingly did several experiments on P. monodon which were collected from different areas in the world. Dr. Tang also generously provided us some suspicious samples which ever gave false-positive test results. From those experiments, we found that there were 5 % to 8% false-positive results will coming out from applying IQ2000TM IHHNV detection kit on African and Australian P. monodom. The false-positive result was occurred by the mismatch of primers with the IHHNV-related sequence.
In order to provide best molecular biological diagnostic tool to customers, we re-analyzed DNA sequences, and designed primers to avoid the confusing DNA sequences in the virus and P. monodon. After our exertions in past months, we can announce proudly that the advanced version of IQ2000TM IHHNV detection kit, IQ2000TM IHHNV_nested, is available! With the newly developed system, not only the false-positive results of African and Australian P. monodon diagnosis can be avoided, but also the detection sensitivity will be increased to 10 copies per reaction due to its application of nested PCR.
In addition, except conventional PCR-based IQ2000TM, IQ REAL IHHNV is also a practical tool in IHHNV diagnosis.
According to the mechanism of TaqMan probe, the fluorescent signal only appears when it is cleaved by Taq DNA polymerase in reaction proceedings. The fixed reaction condition of the system also prevents the mis-matching of the gene-specific probe if the sequence is not completely complementary. That makes the fidelity of the IQ REAL system become much higher than conventional PCR. Therefore, the IHHNV-related sequence will not be any concern when IQ REAL IHHNV is used in diagnosing African and Australian P. monodon.
Farming IntelliGene always show appreciation to all the researchers’ efforts for decoding the shrimp and virus nucleic acid sequence. We will also do our best to modify and update our products accordingly as soon as possible. For the alternatives of IHHNV diagnosis, IQ2000TM IHHNV_nested and IQ REAL IHHNV, please refer to our website for more detailed information.