[ABO blood grouping of fingerprint by means of immunohistochemical procedure].

For the purpose of ABO-blood typing on fingerprints, the detection of blood group substances in fingerprints attached on nitrocellulose filter or paper was performed immunohistochemically using avidin-biotin-peroxidase complex (ABC) method. At first, it was fundamentally tested whether ABO-blood typing could be specifically performed for the fingerprints of known ABO blood group, being made experimentally on nitrocellulose filter or paper, and the effect of fixation and paper quality for the detection was also examined. And, ABO-typing was carried out using transferred fingerprints from a slide glass to a nitrocellulose filter. Moreover, using a fingerprint of unknown ABO-type, serially repetitive blood typing (three times) was compared to individually performed grouping (three tests) after dividing a single fingerprint into three parts. In addition, the method of serial ABO-blood typing after the morphological detection of fingerprints by ninhydrine was also considered. As results, according to primary antibodies applied, ABH activities were specifically detected in the fingerprints on nitrocellulose filter and paper. For the fixation procedure of very minute blood group substances to paper, heat fixation was the most effective and methanol fixation was also available. The intensity of immunostaining of fingerprints decreased according to the deterioration of paper quality used. And, the transferred fingerprints on nitrocellulose filter were also specifically typed. Serially repetitive blood typing (anti-B-->anti-A-->anti-H) was possible to fingerprints on nitrocellulose filter, but it gave poor results to those on paper. To overcome this difficulty, after being detected morphologically by ninhydrine, iodine or aluminium powder and decolored thereafter, a fingerprint on paper was divided into three parts and specific blood typing was possible. As for the double blind test to fingerprints on paper, 22 out of 35 fingerprints were specifically typed and the rate of correct typing was 62.9%. From these results, it can be considered that this method is available for ABO-typing of fingerprints of secretor type in forensic practice.