OBSERVATIONS ON POLYMERASE CHAIN-REACTION AMPLIFICATION OF INFECTIOUSBURSAL DISEASE VIRUS DSRNA

Two methods for denaturing double stranded (ds)RNA of infectious bursa l disease virus for the purpose of reverse transcribing it were compar ed: Heat denaturation at 65 degrees C in the presence of DMSO and in t he absence of DMSO. As part of the analysis, the nature of cDNA in the two preparations was examined by polymerase chain reaction (PCR) ampl ification, firstly by varying the number of cycles of PCR, and secondl y by re-amplification of serial dilutions of the reaction products. Th e results show that denaturation of dsRNA in the presence of DMSO (met hod 1) is superior to denaturation without DMSO (method 2) judging by the yield of a specific PCR fragment after 30 cycles, and that the pro ducts of method 2 can be re-amplified, albeit poorly, with the generat ion of heterologous products.