Efficient and reliable PCR-based detection of the ABO blood group alleles: genotyping on stamps and other biological evidence samples.

PCR-based ABO genotyping was established using restriction enzyme digestion followed by horizontal polyacrylamide gel electrophoresis and silver staining. The method described here is fast, with results obtained within hours, not days, it obviates the need for radioisotopes and can be performed with 1-2 ng of extracted genomic DNA. ABO blood group determination was successful in various types of biological materials of forensic interest such as bloodstains, vaginal swabs, cigarette butts, and hair roots. Moreover, after preincubation in distilled water, DNA (2-8 ng) was extracted from 12 up to 10-years-old stamps and was correctly typed at the ABO locus. The results presented here indicate that the PCR-based ABO genotyping is a fast, sensitive, reliable, and economic method providing blood group determination in DNA from a variety of different types of specimens. It can provide determination from specimens of limited amount and/or with partially degraded DNA as well. Therefore, it is very useful for first-step suspect screening as well as in forensic research for the analysis of biological evidence.