Detection of hemagglutinins in dried saliva stains and their potential use in blood typing

Since 1928, hemagglutinins have been known to exist in saliva; however, they have not been utilized as evidence in criminal investigations because in the past, techniques for measuring them have not been sufficiently sensitive. In this paper we describe improved techniques for detecting salivary hemagglutinins and report initial results obtained with these methods. The stability of salivary hemagglutinins at several different temperatures was examined in liquid samples and in dried stains on filter paper, cigarette butts, and envelope flaps. Our observations indicate that salivary hemagglutinins may be sufficiently stable, over periods of one to several days at ambient room temperatures, to be of value to forensic science investigators. The results of the hemagglutinin assay are not affected by the age or sex of the sample donor. Because salivary hemagglutinins can be used to determine ABO blood type, analyses of this kind can serve as an important confirmatory test which the forensic serologist can use in conjunction with salivary agglutinogen determinations.