Application of the GPT system in paternity cases.

Experiments show that the GPT starch gel pattern of any given blood sample is fully reproducible, and that an individual's GPT type is constant at least after the age of 1 month. GPT isoenzyme patterns are influenced and may be changed during storage of unfrozen blood. The interval between sampling and preparation of haemolysate should therefore not exceed 4 days. In haemolysates kept at -25 degrees C the isoenzyme patterns remain unchanged for at least many months. The GPT system forms a valuable means for statistical information in paternity cases. Thus, the overall chance is 18.7% for paternity exclusion or strong evidence against paternity for a falsely alleged father. Based on a material of 1,316 paternity cases, it is concluded that the GPT system is a valuable supplement to other systems of genetic markers in cases of disputed paternity.