[The genotyping of reassortants of the influenza virus type B]

A rapid method requiring a small amount of materials is described for genotyping of influenza type B virus reassortants. It allows one to carry out within a short time a simultaneous analysis of the genome of 12 virus strains by PAG electrophoresis of virion RNAs. The conditions for the detection of the greatest strain-specific differences in the mobility of individual RNA segments of influenza B virus were found: 3.3% PAG plus 4.5 M urea, although the most reliable results were obtained by comparisons in gels with various acrylamide-urea ratios.