Abstract: A method of assaying genetic sequences comprises introducing double stranded DNA to be assayed into an aqueous buffer medium containing complexes of an anchor DNA strand anchored to a support matrix and hybridized with a reporter DNA strand having a detectable label. A portion of the anchor strand or the reporter strand consists of a selected sequence of bases capable of forming a triple helix or triple strand structure with a portion of particular double stranded DNA. The reporter strand is displaced from the complex upon formation of a triple helix or triple strand structure, and displaced reporter strands are detected to determine the presence of the particular double stranded DNA. Gene probes, anchor/reporter hybrids, selected gene sequences and kits, useful in the assay method, are provided.

Abstract: Viruses are detected by means of an immunoassay method in which an extended solid phase coated with antiviral antibody is employed to bind and remove virions from a specimen by forming an immuno-complex with antigens of said virions, a mobile solid phase comprising a dispersion of microspheres coated with the antiviral antibody is used to bind said microspheres to antigens associated with said immuno-complex, and the presence of bound microspheres is detected. The detection sensitivity is amplified by the ability to more readily detect the microspheres, which may be dyed or labelled. The extended solid phase advantageously may be in the form of a dipstick which can be easily contacted with the specimen. A virus detection kit provides the extended solid phase and mobile solid phases, each coated with antiviral antibodies.