Method for Detecting Genetic Polymorphism

A method for detecting a genetic polymorphism of apolipoprotein E present in genomic DNA collected from a subject, comprising the following steps 1 to 3:

• 1. a step of releasing a DNA from exocrine fluid or mucus containing epithelial cells collected from a subject and preparing a specimen containing the DNA;
• 2. a step of adding the followings to the specimen containing the DNA and then mixing:
• (1) a PCR enzyme,
• (2) a PCR primer pair for amplifying a nucleic acid fragment of the apolipoprotein E gene containing a codon encoding the 112th or 158th amino acid residue (Cys or Arg) of apolipoprotein E, and
• (3) a set consisting of a fluorescent labeled probe which has an oligonucleotide that binds to a nucleic acid fragment of the apolipoprotein E gene, containing a codon encoding wild-type Cys which is the 112th amino acid residue of apolipoprotein E, and a fluorescent labeled probe which has an oligonucleotide that binds to a nucleic acid fragment of the apolipoprotein E gene, containing a codon encoding mutant Arg which is the 112th amino acid residue of apolipoprotein E, wherein the fluorescent dyes used for labeling are different from each other,
• or a set consisting of a fluorescent labeled probe which has an oligonucleotide that binds to a nucleic acid fragment of the apolipoprotein E gene, containing a codon encoding wild-type Arg which is the 158th amino acid residue of apolipoprotein E, and a fluorescent labeled probe which has an oligonucleotide that binds to a nucleic acid fragment of the apolipoprotein E gene, containing a codon encoding mutant Cys which is the 158th amino acid residue of apolipoprotein E, wherein the fluorescent dyes used for labeling are different from each other;
• and
• 3. a step of performing PCR on the said mixture and measuring the fluorescence intensity from the PCR product corresponding to the 112th or 158th amino acid residue of apolipoprotein E of the said subject.