A PCR-RESTRICTION ENZYME TECHNIQUE FOR DETERMINING DENGUE VIRUS SUBGROUPS WITHIN SEROTYPES

The polymerase chain reaction (PCR) and restriction enzyme analysis we re used to develop a rapid and simple procedure for identifying geogra phic subgroups of dengue virus within serotypes for epidemiologic inve stigations. The entire structural protein region of dengue viruses was amplified and the products were digested with the endonucleases AluI or DdeI. By comparing the restriction fragment length polymorphisms (R FLPs), we recognized dengue-2 and dengue-3 subgroups that corresponded to those previously determined by oligonucleotide fingerprinting or g enomic sequencing. This procedure can be performed in 2 days without t he use of radioisotopes, and results can be interpreted without comput er analysis. For those analyses which require only subgroup affiliatio ns, this is a useful tool for rapidly screening multiple virus isolate s.