Abstract: A method of quantitating genomic DNA in a sample is provided. The method comprises the steps of adding to the sample a given amount of at least one nucleic acid as an internal standard, wherein the standard nucleic acid differs from the genomic DNA to be quantified in at least one detectable characteristic; amplifying the genomic DNA and the internal standard nucleic acid by means of a nucleic acid amplification process employing primers complementary to repetitive genomic sequences; determining as a first amount the amount of amplified genomic DNA, and determining as a second amount the amount of amplified standard nucleic acid; and determining from the first and second amounts, as a third amount, the amount of genomic DNA originally contained in the sample. Kits for performing the method and products substantially free of foreign DNA as determined by the method also are provided.

Abstract: There is disclosed a method of quantitating nucleic acids in a sample by using nucleic acid amplification, wherein, prior to the amplification step, a given amount of a known nucleic acid molecule is added to the sample as internal standard, which standard nucleic acid molecule differs from the nucleic acid to be quantitated by at least one detectable characteristic; to obtain a high precision and good reproducibility, known amounts of at least two known nucleic acid molecules which differ from each other and from the nucleic acid to be quantitated in at least one detectable characteristic are added as an internal standard to the sample prior to nucleic acid amplification, the amounts of amplified sample and standard nucleic acids obtained are determined, and from the amounts obtained, the amount of the nucleic acid to be quantitated originally present in the sample is determined.