[The HL-A system in cases of disputed paternity with regard to the value of proof (percentage accuracy) (author's transl)].

The practical experience in 33 cases of disputed paternity (34 children; 26 cases with only one accused man, 7 cases with more than one) in regard to the HL-A system to find nonpaternity is compared with 18 conventional hereditary systems used in paternity cases. The high efficiency of HL-A for the biostatistical calculation of the probability of paternity (Essen-Moller formula) is also demonstrated. The mode of inheritance of the HL-A system is well known (maximal error below 1 per cent), which means that the value of proof (percentage accuracy) in disputed paternity cases is 99 per cent. The value of proof, however, is increased if, in a certain case, the nonpaternity is also found in another hereditary blood group system.