CHEMICAL METHOD FOR THE ANALYSIS OF DNA SEQUENCES

摘要

The invention provides a method of identification of the base in a target position in a DNA sequence wherein sample DNA is subjected to amplification; the amplified DNA is immobilised and then subjected to strand separation, the non-immobilised strand being removed and an extension primer, which hybridis es to the immobilised DNA immediately adjacent to the target position; is provided; each of four aliquots of the immobilised singl e stranded DNA is then subjected to a polymerase reaction in the presence of a dideoxynucleotide, each aliquot using a different dideoxynucleotide whereby only the dideoxynucleotide complementary to the base in the target position becomes incorpored; the fou r aliquots are then subjected to extension in the presence of all four deoxynucleotides, whereby in each aliquot the DNA which has not reacted with the dideoxynucleotide is extended to form double stranded DNA while the dideoxy-blocked DNA remains a s non-extended DNA; followed by identification of the double stranded and/or non-extended DNA to indicate which dideoxynucleotide was incorporated and hence which base was present in the target position.