Abstract: The present invention provides a method for detecting nucleotide polymorphism contained in a sample wherein nuclease activity and legase activity are employed at the same time.

Abstract: A method of detecting variation or polymorphism in a nucleic acid sequence, which is useful particularly in diagnosing a hereditary disease, analyzing nucleotide polymorphism, etc., and primers to be used therein. More particularly speaking, this method comprises treating a primer for wild type and one or two primers for variant with DNA polymerase either simultaneously or separately, and detecting the nucleotide polymorphism contained in the nucleic acid sample by judging whether or not the primers are extended, or whether or not the primers are amplified with a reverse primer. In this method, the 3′-end second bases of the primer for wild type and one or two primers for variant correspond to respective nucleotides anticipated in the nucleotide polymorphism site. Further, at least one of the bases from the 3′-end third position to the 5′-end is substituted by a base not complementary to the base in the chain hybridized with the primer in the chromosome or fragment.

Abstract: Methods for nucleic acid amplification with thermostable ribonuclease H, in which single-stranded RNA (-) is prepared from RNA (+) as a target nucleic acid and the copy number of the single-stranded RNA (-) is increased through the use of thermostable ribonuclease H in combination with non-thermostable RNA-dependent DNA polymerase, non-thermostable DNA-dependent DNA polymerase and non-thermostable DNA-dependent RNA polymerase. In these methods, the number of amplification cycles is well increased and the sensitivity of detection can, therefore, be improved, as compared with the conventional methods. Also provided are methods for the detection of a target nucleic acid from RNA copies of a specific nucleic acid, obtained by any of the amplification methods, and reagent kits for use in these methods.

Abstract: The present invention relates to two primers for amplifying a cytomegalovirus (CMV) nucleic acid suitable for a nucleic acid sequence-based amplification (NASBA) using a DNA-dependent RNA polymerase, a first primer containing a promoter sequence and a nucleic acid sequence consisting of at least fifteen continuous bases selected from the nucleic acid sequence of SEQ ID NO:1; a second primer containing a nucleic acid sequence consisting of at least fifteen continuous bases selected from the nucleic acid sequence of SEQ ID NO:2, NO:3 or NO:4; a detecting probe and/or a capturing probe containing a nucleic acid sequence consisting of at least continuous fifteen bases selected from the nucleic acid sequence(s) of SEQ ID NO:5, NO:6 and/or NO:7 wherein said sequence is modified if necessary; a reagent kit for detecting a CMV containing the above-mentioned primers and probes; and a nucleic acid sequence-based amplification (NASBA) using said primers.

Abstract: An oligonucleotide is provided, which has at least a base sequence A, which is 10-30 nucleotides in length and homologous to a part of a specific nucleic acid sequence to be amplified, and a base sequence B, which is 10-30 nucleotides in length and complementary to a sequence 3' to the part of the specific nucleic acid sequence to be amplified. Sequences A and B are separated by a spacer region of 0-20 nucleotides. The oligonucleotide is used in an amplification method, wherein the oligonucleotide is mixed with a sample containing a specific nucleic acid sequence to be amplified and allowed to anneal to the specific nucleic acid sequence in the sample. The annealed oligonucleotide acts as a primer in an elongation reaction, whereas any nonannealed oligonucleotide is decomposed, except for at least part of the base sequence A. The elongation product is then denatured to a single strand for use as a template to which the remaining oligonucleotide anneals to form a primer for subsequent elongation.