Patent ID: 6410278
Filing Date: 2002-06-25
Classification: C12N,C12Q

Abstract:
A method of amplifying a nucleic acid comprising:A) providing a template having (i) a 3â€² end portion comprising a first region located 3â€² terminal and a first complementary region which, under suitable conditions, anneal to one another to form a first loop, (ii) a 5â€² end portion comprising a second region located 5â€² terminal and a second complementary region which, under suitable conditions, anneal to one another to form a second loop, and (iii) a region connecting the 3â€² end portion and the 5â€² end portion; B) extending the 3â€² terminal of the template to the 5â€² end of the template by means of a polymerase having strand displacement activity, when the first region and first complementary region are annealed to one another to form the first loop, to form a template extension which includes a third region located 3â€² terminal and a third complementary region which arc substantially the same as the second complementary region and second region, respectively, and which, under suitable conditions, anneal to one another to form a third loop; C) annealing to the first loop of the extended template an oligonucleotide primer comprising at the 3â€² terminal a nucleotide sequence complementary to at least part of the first loop and at the 5â€² terminal a nucleotide sequence complementary to the first region of the template; D) extending the oligonucleotide primer along the extended template, by means of a polymerase having strand displacement activity, to form a new template complementary to the template, thereby displacing the template extension formed during said extending in step B); E) Further extending the 3â€² terminal of the extended template to the 5â€² end of the extended template by means of a polymerase having strand displacement activity, when the third region and the third complementary region are annealed to one another to form the third loop, thereby displacing the new template from the extended template; and F) repeating steps A)-E) using the new template as the template in step A), thereby amplifying the nucleic acid.