Application of plasminogen polymorphism to forensic hemogenetics.

Plasminogen polymorphism (PLG) has attained considerable importance in forensic hemogenetics. PLG comprises two common, codominant autosomal alleles, PLGA and PLGB, more than 18 variants, and the silent allele PLGQ0. Isoelectric focusing followed by functional or immunochemical detection seems to be the optimal method for the determination of phenotypes. PLGA is the most common allele in all populations, having its highest frequency in Mongoloids, Amerindians and Eskimos, the lowest in Caucasoids. The functionally inactive plasminogen M5 so far has been seen exclusively in Japanese individuals. Silent PLG alleles were only observed in the heterozygous state. No clear differences in functional activity or plasma level could be ascertained for any of the other allotypes. PLG polymorphism is now widely used for many haemogenetic investigations. From the allele distribution in European Caucasoids a single exclusion chance of 17.2% for non-fathers in paternity testing may be calculated. The major prerequisites of a new genetic marker in the parentage expertise, established Mendelian inheritance, favorable distribution of common alleles, low frequency of silent alleles, and simple reproducible typing technology, are fulfilled.