Abstract: The present invention provides a method for determining the nucleic acid composition in a total nucleic acid mixture comprising a first nucleic acid and a second nucleic acid. The method comprises: 1) treating the total nucleic acid mixture with a bisulfate, to convert the non-methylated cytosine in the total nucleic acid mixture into uracil, and obtain a converted total nucleic acid mixture; 2) subjecting the converted total nucleic acid mixture to multiplexed fluorescent quantitative PCR using a first set of amplification primers and a second set of amplification primers; and 3) based on the ratio R of the methylated amplification product to the non-methylated amplification product of the predetermined nucleic acid fragment, a methylation proportion M1 of the predetermined nucleic acid fragment in the first nucleic acid, and a methylation proportion M2 of the predetermined nucleic acid fragment in the second nucleic acid, determining the nucleic acid composition in the total nucleic acid mixture.

Abstract: The present invention provides a method for determining the nucleic acid composition in a total nucleic acid mixture comprising a first nucleic acid and a second nucleic acid. The method comprises: 1) treating the total nucleic acid mixture with a bisulfate, to convert the non-methylated cytosine in the total nucleic acid mixture into uracil, and obtain a converted total nucleic acid mixture; 2) subjecting the converted total nucleic acid mixture to multiplexed fluorescent quantitative PCR using a first set of amplification primers and a second set of amplification primers; and 3) based on the ratio R of the methylated amplification product to the non-methylated amplification product of the predetermined nucleic acid fragment, a methylation proportion M1 of the predetermined nucleic acid fragment in the first nucleic acid, and a methylation proportion M2 of the predetermined nucleic acid fragment in the second nucleic acid, determining the nucleic acid composition in the total nucleic acid mixture.