[Typing of DNA using the primer extension preamplification (PEP) method--studies of reliability of typing and detection limits].

Primer extension preamplification (PEP), which can amplify sequence-independently a limited quantity of DNA as a whole, allows multiple DNA analyses by polymerase chain reaction (PCR). This technique may be applicable to forensic cases, especially in cases where only small amounts of DNA are available. To define the accuracy and sensitivity of PEP, the DNA typing results of nine loci (TH01, MCT118, HLA-DQ alpha, amelogenin, LDLR, GYPA, HBGG, D7S8, GC) by PCR with PEP (PEP-PCR) were compared with those by PCR without PEP. Both results were identical to each other for each sample tested. Furthermore, amplification of an initial genomic DNA by PEP was found to range from 15 to 600 times of the initial quantity and the efficiency of PEP may depend on the sequences flanking the loci tested. These results indicate that PEP can increase typing potential of PCR from forensic samples.