Competitor primer asymmetric polymerase chain reaction

A process for amplifying an unknown or known staffing amount of a double-stranded nucleic acid segment having first and second complementary strands to produce single-stranded nucleic acid in an amount that is proportional to the starting amount of the nucleic acid segment, which comprises:

• (a) symmetrically amplifying the nucleic acid segment to generate a double-stranded nucleic acid product in an amount that is proportional to the starting amount of the nucleic acid segment, wherein the symmetrical amplifying is carried out by thermal cycling a reaction mixture comprising:
• (i) the nucleic acid segment,
• (ii) a first primer for annealing to the first complementary strand at a first primer specific binding site,
• (iii) a second primer, which is different from the first primer, for annealing to the second complementary strand at a second primer specific binding site,
• (iv) a nucleotide for each of adenine, guanine, cytosine and thymine,
• (v) a reaction buffer, and
• (vi) a thermally stable polymerase for extending annealed primers,
• (b) asymmetrically amplifying the double-stranded nucleic-acid product to generate a single-stranded nucleic acid product in an amount that is proportional to the amount of double-stranded product generated by the symmetrical amplifying, wherein the asymmetrical amplifying comprises:
• (i) adding a competitor primer to the reaction mixture, wherein the competitor primer prevents one of the first and second primers from annealing to the first or second complementary strands and is incapable of being extended by the polymerase, and
• (ii) continuing the thermal cycling.