GEDAP method (genotyping based on diagnostic amplification products) for detecting and/or preventing genotyping errors from amplification products of a polymorphic focus

A method for at least one of detecting and preventing genotyping errors due to total or partial non-amplifications of a polymorphic locus, the method comprising the following steps:

• a) obtaining a nucleic acid originating from at least one eukaryotic cell;
• b) amplifying a nucleic acid sequence by PCR which allows the denaturation of double-stranded nucleic acids and their subsequent renaturation for inducing generation of homoduplexes of amplified alleles and other diagnostic additional products (DAPs) that are specific for at least one of homozygotes (DAPs-HOM), heterozygotes (DAPs-HET) and alleles (DAPs-AL), wherein said DAPs are additional amplification products specific to at least one genotype or allele resulting from at least one of an alteration of the sequence of the DNA template, a formation of intermolecular complexes and confonnational changes of amplification products;
• c) detecting the amplification products by an analytical procedure under non-denaturing conditions that favor at least one of the maintenance of homoduplexes and DAPs generated in PCR, and the maintenance of new DAPs generated once the PCR has finished by denaturing the amplification products by physical, chemical or biological procedures and subsequent renaturing;
• and
• d) performing the genotyping on the basis of the joint analysis of identified homoduplexes and DAPs wherein genotyping errors of genuinely heterozygous samples as homozygous samples due to total or partial non-amplifications are detected from the absence of DAPs specific to homozygotes (DAPs-HOM) and genotyping errors of genuinely heterozygous samples as homozygous samples due to total or partial non-amplifications are prevented from the presence of at least one of DAPs specific to alleles (DAPs-AL) and of heterozygotes (DAPs- HET).